csl.rnc

namespace a = "http://relaxng.org/ns/compatibility/annotations/1.0"
namespace atom = "http://www.w3.org/2005/Atom"
namespace cs = "http://purl.org/net/xbiblio/csl"
namespace dc = "http://purl.org/dc/elements/1.1/"
namespace sch = "http://www.ascc.net/xml/schematron"
namespace xhtml = "http://www.w3.org/1999/xhtml"

# CSL schema metadata

dc:title [ "Citation Style Language" ]
dc:creator [ "Bruce D'Arcus" ]
dc:creator [ "Simon Kornblith" ]
dc:contributor [ "Frank Bennett" ]
dc:contributor [ "Rintze Zelle" ]
dc:copyright [ "Bruce D'Arcus and Simon Kornblith, 2007-2011" ]
dc:rights [ "Permission to freely use, copy and distribute." ]
dc:description [
    "Citation Style Language (CSL) schema for describing bibliographic and citation formatting."
]

start = independent-style | dependent-style | locale

## Subparts of the CSL schema
include "csl-terms.rnc"
include "csl-types.rnc"
include "csl-variables.rnc"
include "csl-categories.rnc"

# Embedded Schematron rules to detect undefined macro-calls in cs:text, cs:key

sch:ns [
    uri = "http://purl.org/net/xbiblio/csl"
    prefix = "cs"
    ]
sch:pattern [
    name = "Non-existing macros"
    sch:rule [
        context = "//cs:text[@macro]"
        sch:assert [
            test = "@macro = /cs:style/cs:macro/@name"
            "This macro call has no corresponding macro."
        ]
    ]
    sch:rule [
        context = "//cs:key[@macro]"
        sch:assert [
            test = "@macro = /cs:style/cs:macro/@name"
            "This macro call has no corresponding macro."
        ]
    ]
]

## Independent CSL style
div {
    independent-style =
        element cs:style {
            
            ## Default style locale (optional)
            attribute default-locale { xsd:language }?,
            
            ## Style type (in-text citations or note-based)
            attribute class { "in-text" | "note" },
            
            style-options,
            version,
            info,
            (style-locale* & macro* & citation & bibliography?)?
        }
}
## Dependent CSL style
div {
    dependent-style =
        element cs:style {
            version,
            info-dependent-style
        }
}
[ a:documentation [ xhtml:h2 [ "Style Metadata" ] ] ]
div {
    
    ## The version of the CSL schema with which the style is compatible.
    version = attribute version { "1.0" }
    
    ## The Content model for CSL metadata is borrowed from Atom.
    info =
        element cs:info {
            info-author*
            & info-category*
            & info-contributor*
            & info-id
            & info-issn*
            & info-issnl?
            & info-link*
            & info-published?
            & info-rights?
            & info-summary?
            & info-title
            & info-title-short?
            & info-updated
        }
    
    info-dependent-style = 
        element cs:info {
            info-category*
            & info-id
            & info-issn*
            & info-issnl?
            & info-link-dependent-style+
            & info-published?
            & info-summary?
            & info-title
            & info-title-short?
            & info-updated
        }

    info-author = element cs:author { info-contributor-pattern }
    info-contributor = element cs:contributor { info-contributor-pattern }
    info-contributor-pattern =
        element cs:name { text }
        & element cs:email { text }?
        & element cs:uri { xsd:anyURI }?

    ## The category element may be used to specify the citation format of the
    ## style (using the citation-format attribute) and the fields or disciplines
    ## for which the style is relevant (using the field attribute).
    info-category =
        element cs:category {
            attribute citation-format { info-format-categories }
            | attribute field { info-field-categories }
        }
    
    ## As in Atom, the cs:id element is a required URI that is globally-unique
    ## and persistant. To allow styles to be automatically updated, the URI of a
    ## style should not change once assigned. Ideally, the URI resolves to the
    ## correct CSL file: it should preferably point to the CSL style itself in
    ## case of independent styles, and to the independent-parent style in case
    ## of dependent styles.
    info-id = element cs:id { xsd:anyURI }
    
    info-link =
        element cs:link {
            attribute href { xsd:anyURI },
            
            ## For transformation to Atom, the rel values should be expanded to
            ## include the base URI <http://purl.org/net/xbiblio/csl/relations#>.
            attribute rel {
                
                ## The URI of the CSL style itself.
                "self"
                | 
                  ## The CSL style URI from which the current style is derived.
                  "template"
                | 
                  ## A documentation URI for the style.
                  "documentation"
            },
            info-text
        }
    
    info-link-dependent-style =
        element cs:link {
            attribute href { xsd:anyURI },
            
            ## For transformation to Atom, the rel values should be expanded to
            ## include the base URI <http://purl.org/net/xbiblio/csl/relations#>.
            attribute rel {
                
                ## The URI of the CSL style itself.
                "self"
                | 
                  ## The CSL style URI whose content should be used for
                  ## processing. Required for dependent styles.
                  "independent-parent"
            },
            info-text
        }
    
    ## Typically, the date of initial creation or first availability
    info-published = element cs:published { xsd:dateTime }
    info-rights = element cs:rights { info-text }
    info-summary = element cs:summary { info-text }
    info-title = element cs:title { info-text }
    
    ## For abbreviated titles (e.g. "APA")
    info-title-short = element cs:title-short { info-text }
    info-text =
        attribute xml:lang { xsd:language }?,
        text
    
    ## For journal-dedicated styles the journal's ISSNs or ISSN-L may be included.
    ## A valid ISSN(-L) consists of: four digits, a hyphen, three digits, and a 
    ## check digit, which can be a numeral digit or a roman X, e.g. "1234-1231".
    info-issn =
        element cs:issn {
            xsd:string { pattern = "\d{4}\-\d{3}(\d|x|X)" }
        }
    info-issnl =
        element cs:issnl {
            xsd:string { pattern = "\d{4}\-\d{3}(\d|x|X)" }
        }
    
    ## a required update date-time stamp; for example, 2007-10-26T21:32:52+02:00
    info-updated = element cs:updated { xsd:dateTime }
}
[ a:documentation [ xhtml:h2 [ "Localization" ] ] ]
div {
    
    ## CSL locale file (locales-xx-XX.xml)
    locale =
        element cs:locale {
            
            ## Specifies the locale of the locale file.
            attribute xml:lang { xsd:language },
            
            ## Indicates with which version of the CSL schema the locale file is compatible
            attribute version { "1.0" },
            
            (localized-terms & localized-dates+ & localized-options)
        }
    
    ## In styles, cs:locale can be used to override localized terms, dates and options.
    style-locale =
        element cs:locale {
            
            ## Specifies the locale to override. A cs:locale element without the
            ## xml:lang attribute can also be used: it overrides the content of
            ## all locales, but is in turn overridden by cs:locale elements with
            ## the xml:lang attribute.
            attribute xml:lang { xsd:language }?,
            
            (localized-terms? & localized-dates* & localized-options?)
        }
    localized-terms = element cs:terms { (simple-term | compound-term)+ }
    term-attributes =
        attribute form { cs-term-forms }?,
        attribute name { cs-terms }

    ## "verb-short" reverts to "verb" if the "verb-short" form is not available
    ## "symbol" reverts to "short" if the "symbol" form is not available
    ## "verb" and "short" revert to "long" if the specified form is not available
    cs-term-forms = "long" | "verb" | "short" | "verb-short" | "symbol" | cs-term-forms.extension
    
    ## Extension structures. You may override these in a customization 
    ## schema. If you do, please contact the xbiblio project to add 
    ## the term or form to the formal controlled list in the schema.
    div {
        cs-terms.extension = notAllowed
        cs-term-forms.extension = notAllowed
    }
    
    ## Simple terms are basic strings, used to represent genres, media, etc.
    simple-term = element cs:term { term-attributes, text }
    
    ## Compound terms are those whose output can be either singular or plural. 
    ## Typically used for things like page number or editor labels.
    compound-term = element cs:term { term-attributes, single-term, multiple-term }
    multiple-term = element cs:multiple { text }
    single-term = element cs:single { text }
    
    ## Instances of cs:date for which the form attribute is set are localized
    ## by default. Localized date formats can be overridden.
    localized-dates =
        element cs:date {
            
            ## Declares the type of date being defined.
            attribute form {
                
                ## Text form of the date (e.g. "December 15, 2005" for en-US).
                "text"
                | 
                  ## Numeric form of the date (e.g. "12-15-2005" for en-US)
                  "numeric"
            },
            
            ## No affixes may be applied to cs:date in cs:locale
            font-formatting,
            delimiter,
            element cs:date-part {
                affixes, text-case, font-formatting, (month | day | year)
            }+
        }
    
    ## Locale specific options.
    localized-options =
        
        ## Localized global options are specified as attributes in the
        ## cs:style-options element. If future versions of CSL include localized
        ## options that are citation or bibliography specific, the elements
        ## cs:citation-options and cs:bibliography-options can be added.
        element cs:style-options {
            
            ## Determines whether punctuation (commas and periods) goes within 
            ## the quotation marks, or outside (default).
            attribute punctuation-in-quote { xsd:boolean }?
        }
}
[ a:documentation [ xhtml:h2 [ "Macros" ] ] ]
div {
    
    ## The macro element works something like in BibTeX, and provides a ready-made 
    ## bundle of formatting templates that can be easily reused elsewhere.
    macro =
        element cs:macro {
            attribute name { xsd:NMTOKEN },
            cs-element+
        }
}
[ a:documentation [ xhtml:h2 [ "Citation and Bibliography" ] ] ]
div {
    
    ## The cs:citation handles printing of citations. A citation may consist of
    ## one or more references to bibliographic sources. These references can either
    ## be simple in-text keys [doe99] or numeric markers [1], or more complex short
    ## descriptors common in author-date (Doe, 1999a) or note styles.
    citation = element cs:citation { (citation-options & sort?), citation-layout }
    
    bibliography = element cs:bibliography { (bibliography-options & sort?), bibliography-layout }
    
    citation-layout = element cs:layout { affixes, font-formatting, delimiter, cs-element }
    bibliography-layout = element cs:layout { affixes, font-formatting, cs-element }
    cs-element = (names | date | label | cs-text | cs-number | choose | group)+
}
[ a:documentation [ xhtml:h2 [ "Contributor Names" ] ] ]
div {
    ## Options for cs:names, available for cs:style, cs:citation and cs:bibliography.
    names-opt =
        ## Delimiter between names (delimiter between variables is on <names>
        ## tag, where it should be). This is ", " in "J. Doe, S. Smith."
        attribute names-delimiter { text }?
    
    names-attributes =
        affixes,
        display,
        font-formatting,
        
        ## the delimiter between name groups
        delimiter,
        attribute variable {
            list { cs-names+ }
        }
    
    ## Options for cs:name, available for cs:style, cs:citation and cs:bibliography.
    name-opt =
        name-attributes,
        
        ## Indicates long (first name + last name, for Western names) or short
        ## (last name only, for Western names) form of name. Default is long
        ## form. The "count" form is used to return the count of the contributor
        ## list, and may be used in special sorting routines.
        attribute name-form { "long" | "short" | "count" }?,
        
        ## Delimiter between names (delimiter between variables is on <names>
        ## tag, where it should be). This is ", " in "J. Doe, S. Smith."
        attribute name-delimiter { text }?
    
    name-attributes =
        ## Controls appearance of "and"/"&". To disable, do not specify.
        attribute and { "text" | "symbol" }?,
        
        ## Delimiter between the last name rendered and the "et-al" term in case
        ## of et-al abbreviation
        attribute delimiter-precedes-et-al {
        
            ## Default behavior; a space is used for name lists truncated to a
            ## single name. For two or more names, the name delimiter is used:
            ## 1 name: "J. Doe et al."
            ## 2 names: "J. Doe, S. Smith, et al."
            "contextual"
            | 
            ## Name delimiter is always used
            ## 1 name: "J. Doe, et al."
            ## 2 names: "J. Doe, S. Smith, et al."
            "always"
            | 
            ## Name delimiter is never used
            ## 1 name: "J. Doe et al."
            ## 2 names: "J. Doe, S. Smith et al."
            "never"
            }?,
        
        ## Delimiter preceding the last name in a name list
        attribute delimiter-precedes-last {
        
            ## Default behavior; delimiter is included for name lists of length
            ## three or more:
            ## 2 authors: "J. Doe and T. Timmons,"
            ## 3 authors: "J. Doe, S. Smith, and T. Timmons" (note comma preceding 'and').
            "contextual"
            | 
              ## Delimiter is always included
              ## 2 author result: "J. Doe, and T. Timmons"
              ## 3 authors: "J. Doe, S. Smith, and T. Timmons" (note comma preceding 'and').
              "always"
            | 
              ## Delimiter is never included
              ## 2 authors: "J. Doe and T. Timmons,"
              ## 3 authors: "J. Doe, S. Smith and T. Timmons"
              "never"
            }?,
        
        ## Specifies when and how "et al." name list abbreviation is used
        ##   et-al-min: the minimum number of names to use "et al."
        ##   et-al-use-first: the number of names to print before "et al."
        ##   et-al-subsequent-*: as above, but for subsequent citations
        ##   et-al-use-last: when set to "true" ("false" is the default),
        ##   "et al." is replaced by an ellipsis followed by the last name
        attribute et-al-min { xsd:integer }?,
        attribute et-al-use-first { xsd:integer }?,
        attribute et-al-subsequent-min { xsd:integer }?,
        attribute et-al-subsequent-use-first { xsd:integer }?,
        attribute et-al-use-last { xsd:boolean }?,
        
        ## Indicates whether given name parts ought to be given as initials
        ## (e.g., J. K. Rowling) and the text to follow each initial.
        attribute initialize-with { text }?,
        
        ## Sets the author name order to correspond to the sort order of
        ## the bibliography; e.g. Doe, John (name-as-sort-order) vs. John Doe (w/o
        ## attribute).
        attribute name-as-sort-order {
        
            ## Applies name-as-sort-order to first author only.
            "first"
            | 
              ## Applies name-as-sort-order to all authors.
              "all"
            }?,
        
        ## The delimiter for personal name parts where sort order differs from 
        ## display order (for example, in standard Western names). This is the
        ## ", " in "Doe, John."
        attribute sort-separator { text }?
    
    names =
        element cs:names {
            names-attributes,
            ((name, et-al?) & name-label*),
            substitute?
        }
    
    ## Short version of "names" element, without children, allowed in <substitute>
    names-short = element cs:names { names-attributes }
    
    name =
        element cs:name {
            name-attributes,
            affixes,
            font-formatting,
            
            ## Indicates long (first name + last name, for Western names) or short
            ## (last name only, for Western names) form of name. Default is long
            ## form. The "count" form is used to return the count of the contributor
            ## list, and may be used in special sorting routines.
            attribute form { "long" | "short" | "count" }?,
            
            ## Delimiter between names (delimiter between variables is on <names>
            ## tag, where it should be). This is ", " in "J. Doe, S. Smith."
            delimiter,
            
            ## Allows for separate configuration of name part formatting. For example, 
            ## Jane DOE. Order of these elements is not significant.
            element cs:name-part {
                attribute name { "family" | "given" },
                text-case,
                font-formatting
            }*
        }
    
    ## Similar to label as below, but inherits variable from <names> tag
    name-label = element cs:label { label-primitives }
    
    ## Configures formatting of the et al substitution. Only necessary to deviate from 
    ## default rendering (for example, to italicize the string).
    et-al =
        element cs:et-al {
            
            ## term to use for et al substitution; "et-al" is default
            attribute term { "et-al" | "and others" }?,
            affixes,
            font-formatting
        }
    
    ## Substitutions, if the name does not exist
    substitute = element cs:substitute { (names-short | cs-element)+ }
}
[ a:documentation [ xhtml:h2 [ "Dates" ] ] ]
div {
    date =
        element cs:date {
            attribute variable { cs-dates },
            ((
              ## Localized date formats are specified by setting `form`. The
              ## default date format can be changed for all locales by configuring
              ## the date-parts attribute and date-part elements.
              attribute form {
                  
                  ## Use the localized text form of the date (e.g. "December 15, 2005" for en-US).
                  "text"
                  | 
                    ## Use the localized numeric form of the date (e.g. "12-15-2005" for en-US)
                    "numeric"
              }?,
              
              ## The date-parts attribute may be set to show fewer date elements.
              attribute date-parts {
                  
                  ## Year, month and day (default)
                  "year-month-day"
                  | 
                    ## Year and month
                    "year-month"
                  | 
                    ## Year only
                    "year"
              }?,
              
              ## For localized dates, date-part can be used to override layout
              ## options as defined in the locales (except for affixes, which
              ## are locale-specific), e.g. to force the use of leading-zeros,
              ## or the short month form. The inclusion of date-parts does not 
              ## affect which, and in what order, the date-parts are rendered.
              element cs:date-part { text-case, font-formatting, (month | day | year) }*)
             | (
                ## Non-localized dates are formatted by including, in the desired
                ## order, the relevant `date-part`-elements, and by applying formatting,
                ## affixes on cs:date and cs:date-part.
                element cs:date-part {
                    affixes, text-case, font-formatting, (month | day | year)
                }+,
                delimiter)),
            affixes,
            display,
            font-formatting
        }
    
    ## The default delimiter for date ranges is the en-dash.
    ## If the range-delimiter attribute is set for the largest date-part ("day",
    ## "month" or "year") that differs between the two dates of the date range,
    ## its value is used instead.
    range-delimiter = attribute range-delimiter { text }?
    
    ## Month formats:
    ##     long (default): January
    ##     short: Jan
    ##     numeric: 1
    ##     numeric-leading-zeros: 01
    month =
        attribute name { "month" },
        attribute form { "long" | "short" | "numeric" | "numeric-leading-zeros" }?,
        range-delimiter,
        strip-periods
    
    ## Day formats:
    ##     numeric (default): 5
    ##     numeric-leading-zeros: 05
    ##     ordinal: 5th
    day =
        attribute name { "day" },
        attribute form { "numeric" | "numeric-leading-zeros" | "ordinal" }?,
        range-delimiter
    
    ## Year formats:
    ##     long (default): 2005
    ##     short: 05
    year =
        attribute name { "year" },
        attribute form { "short" | "long" }?,
        range-delimiter
    
}
[ a:documentation [ xhtml:h2 [ "Formatting Text" ] ] ]
div {
    
    ## The cs:text element is the main formatting element used to layout down content.
    cs-text =
        element cs:text {
            affixes,
            display,
            font-formatting,
            quotes,
            strip-periods,
            text-case,
            (
             ## render macro output
             attribute macro { xsd:NMTOKEN }
             | (
                ## render localized term
                attribute term { cs-terms },
                attribute form { cs-term-forms }?,
                
                ## term plurality: single ("false", default) or multiple ("true")
                attribute plural { xsd:boolean }?)
             |
               ## render verbatim text.
               attribute value { text }
             | (
                ## render variable
                attribute variable { cs-variables },
                attribute form { "short" | "long" }?))
        }
    
    ## The number markup directive matches the first number found in a field, 
    ## and returns only that component. If no number is detected, the result 
    ## is empty. A non-empty number may be subject to further formatting consisting 
    ## of a form attribute whose value may be numeric, ordinal or roman to format 
    ## it as a simple number (the default), an ordinal number (1st, 2nd, 3rd etc), 
    ## a long-ordinal (first, second, third, etc), or roman (i, ii, iii, iv etc). 
    ## The text-case can also apply to capitalize the roman numbers for instance. 
    ## The other normal formatting rules apply too (font-style, ...). When used 
    ## in a conditional, number tests if there is a number present, allowing conditional 
    ## formatting.
    cs-number =
        element cs:number {
            affixes,
            display,
            font-formatting,
            text-case,
            attribute variable { cs-numbers },
            attribute form { "numeric" | "ordinal" | "roman" | "long-ordinal" }?
        }
}
[ a:documentation [ xhtml:h2 [ "Label Text" ] ] ]
div {
    
    ## The label element is used to print text terms that depend on document content
    ## for pluralization. For labeling pages, this is preferable, as pages may be
    ## either singular or plural (p. or pp.)
    label =
        element cs:label {
            label-primitives,
            attribute variable { "page" | "locator" }
        }
    label-primitives =
        affixes,
        font-formatting,
        text-case,
        strip-periods,
        attribute form { cs-term-forms }?,
        
        ## modifies pluralization behavior (defaults to "contextual")
        attribute plural { "always" | "never" | "contextual" }?
}
[ a:documentation [ xhtml:h2 [ "Groups" ] ] ]
div {
    
    ## cs:group and its child elements are suppressed if a) at least one
    ## rendering element in cs:group calls a variable (either directly or via a
    ## macro), and b) all variables that are called are empty.
    group =
        element cs:group {
            affixes,
            display,
            font-formatting,
            delimiter,
            cs-element+
        }
}
[ a:documentation [ xhtml:h2 [ "Options" ] ] ]
div {
    style-options = 
        demote-non-dropping-particle-opt,
        initialize-with-hyphen-opt,
        page-range-format-opt,
        name-opt,
        names-opt
    citation-options =
        collapse-opt,
        disambiguate-opt,
        note-distance-opt,
        name-opt,
        names-opt
    bibliography-options =
        hanging-indent-opt,
        line-formatting-opt,
        second-field-align-opt,
        subsequent-author-substitute-opt,
        name-opt,
        names-opt
    
    ## Determines whether the non-dropping particle is demoted in inverted
    ## names (e.g. "Koning, W. de"). Defaults to "display-and-sort".
    demote-non-dropping-particle-opt =
        attribute demote-non-dropping-particle { "never" | "sort-only" | "display-and-sort" }?
    
    ## Determines whether compound given names (e.g. "Jean-Luc") are
    ## initialized with (J-L) or without a hyphen (JL). Defaults to true.
    initialize-with-hyphen-opt =
        attribute initialize-with-hyphen { xsd:boolean }?
    
    ## Abbreviation setting of ranges in the page variable
    ## (by default no reformatting is applied to the input data).
    page-range-format-opt =
        attribute page-range-format { "expanded" | "minimal" | "chicago" }?
    
    ## The collapse options control citation collapsing.
    collapse-opt =
        attribute collapse {
            
            ## collapses numeric citations from [1, 2, 3] to [1-3]
            "citation-number"
            | 
              ## collapses cites from (Doe 2000, Doe 2001) to (Doe 2000, 2001)
              "year"
            | 
              ## collapses as "year", but also collapses (Doe 2000a, Doe 2000b)
              ## to (Doe 2000a, b). Collapses as "year" when
              ## disambiguate-add-year-suffix is not set to "true".
              "year-suffix"
            | 
              ## collapses as "year-suffix", but also collapses ranges of
              ## year-suffix markers, so (Doe 2000a, Doe 2000b, Doe 2000c)
              ## becomes (Doe 2000a-c). Collapses as "year" when
              ## disambiguate-add-year-suffix is not set to "true".
              "year-suffix-ranged"
        }?,
        
        ## Specifies the delimiter between year-suffix elements, when
        ## year-suffix collapsing takes place. If not set the delimiter defaults
        ## to that specified for the citation layout.
        attribute year-suffix-delimiter { text }?,
        
        ## Specifies the delimiter following a group of collapsed cites.
        attribute after-collapse-delimiter { text }?
    
    disambiguate-opt =
        
        ## When set true, add further names to uniquely identify the target
        ## source, overriding the constraint imposed by
        ## et-al-subsequent-use-first. The exact rendering of any names added is
        ## determined by applying, in order: the form ("long" or "short"); the
        ## initialize-with attribute, if present; and a given name
        ## disambiguation rule, if disambiguate-add-givenname is set true.
        attribute disambiguate-add-names { xsd:boolean }?,
        
        ## When set true, transform names as required by by the rule specified
        ## by givenname-disambiguation-rule, or use the "all-names" rule by
        ## default. Note that, all of the given name disambiguation rules except
        ## for the "by-cite" rule, a name transformation will affect the way the
        ## name is rendered in multiple references.
        attribute disambiguate-add-givenname { xsd:boolean }?,
        
        ## Adds a year-suffix (e.g., 2007a) when there are two works by the same
        ## author published in the same year included in one bibliography.
        attribute disambiguate-add-year-suffix { xsd:boolean }?,
        
        attribute givenname-disambiguation-rule {
            
            ## The default given name disambiguation rule.  A given
            ## name is first formatted as specified by the attributes
            ## to name (form, initialize-with).  If the resulting name
            ## does not uniquely identify the full name of the
            ## individual, it is progressively transformed in the following
            ## progression, until disambiguation succeeds:
            ## 
            ## 1. "short" becomes "long" + "initialize-with" if the latter is defined
            ## 2. "long" + "initialize-with" becomes "long" if the former is defined
            ## 3. "short" becomes "long"
            ## 
            ## Note that if the name begins in long form with the
            ## given name as initials, step 1 in this list will be
            ## skipped.  Likewise, if the name begins in short form
            ## and the initialize-with attribute is not set, steps
            ## 1 and 2 will be skipped.  If the name begins
            ## in long form, this option will have no effect.
            "all-names"
            | 
              ## Same as the "all-names" rule above, but omitting
              ## steps 2 and 3 of that rule.
              "all-names-with-initials"
            | 
              ## Same as the "all-names" rule above, but ambiguity
              ## is only checked for the first-listed name
              ## source, and only first-listed names are affected
              ## by the transformation.
              "primary-name"
            | 
              ## Same as the "primary-name" rule above, but omitting
              ## steps 2 and 3 of that rule.
              "primary-name-with-initials"
            | 
              ## Apply the transformation described under the "all-names"
              ## rule above, but limit the transformation to the current
              ## source.  The appearance of the name in other references
              ## will not be affected.
              "by-cite"
        }?
    
    ## The number of notes (footnotes or endnotes) within which a
    ## preceding reference to the same source must occur in order for
    ## position="near-note" to be true.  Defaults to 5.
    note-distance-opt = attribute near-note-distance { xsd:integer }?
    
    ## If "true", bibliographic entries are rendered with hanging-indents.
    hanging-indent-opt = attribute hanging-indent { xsd:boolean }?
    
    ## entry-spacing and line-spacing default to 1.
    line-formatting-opt =
        attribute entry-spacing { xsd:integer }?,
        attribute line-spacing { xsd:integer }?
    
    ## Aligns any subsequent lines of a bibliography entry with the beginning
    ## of the second field. If set to "margin", the first field is put in the
    ## margin and all subsequent lines of text are aligned with the margin.
    second-field-align-opt = attribute second-field-align { "flush" | "margin" }?
    
    ## Substitutes subsequent recurrences of an author for a given string.
    subsequent-author-substitute-opt = attribute subsequent-author-substitute { text }?
}
[ a:documentation [ xhtml:h2 [ "Sorting" ] ] ]
div {
    all-variables = cs-variables | cs-dates | cs-names
    
    ## Specifies the sort order within citations or the bibliography. By
    ## default, items are sorted in the order cited.
    sort = element cs:sort { key+ }
    key =
        element cs:key {
            
            (attribute variable { all-variables }
             | attribute macro { xsd:NMTOKEN }),
            
            ## Default sort order is ascending
            attribute sort { "ascending" | "descending" }?,
            
            ## names-min and names-use-first can be used to (further) constrain
            ## the number of names used in a name sort, overriding the values
            ## set on the et-al abbreviation attributes.
            attribute names-min { xsd:integer }?,
            attribute names-use-first { xsd:integer }?,
            
            ## names-use-last can be used to override the value of et-at-use-last
            attribute names-use-last { xsd:boolean }?
        }
}
[ a:documentation [ xhtml:h2 [ "Conditional Statements" ] ] ]
div {
    
    ## The choose elements provides a simple conditional structure.
    choose = element cs:choose { if, else-if*, else? }
    if = element cs:if { condition, cs-element* }
    else-if = element cs:else-if { condition, cs-element* }
    else = element cs:else { cs-element+ }
    condition =
       
        ## The contents of an <if disambiguate="true"> block is only rendered if
        ## it disambiguates two otherwise identical citations. This attempt at
        ## disambiguation will only be made when all other disambiguation
        ## methods have failed to uniquely identify the target source.
        attribute disambiguate { "true" }?,
        
        ## Tests whether the given variables contain numeric data
        attribute is-numeric {
            list { all-variables+ }
        }?,
        
        ## Tests whether the given date variables contain uncertain dates
        attribute is-uncertain-date { 
            list { cs-dates+ }
        }?,
        
        ## Tests whether the locator matches the given locator variables
        attribute locator {
            list { cs-terms.locator+ }
        }?,
        
        ## The boolean operators below indicate the relative position of a 
        ## reference within the document.  These should be checked in 
        ## the order shown below: "first" is true only once, on the first
        ## use of the reference; when "ibid-with-locator" is true, "ibid"
        ## and "subsequent are also true; and when "ibid" is true, "subsequent"
        ## is also true.  The "near-note" operator is true if and only if the
        ## reference has been used within five footnotes (or endnotes, as the 
        ## case may be), counting backward from the current note.  This threshold
        ## may be adjusted using the "near-note-distance" option.  The value of 
        ## "near-note" is *always* false for references that are not in a 
        ## footnote/endnote.
        attribute position {
            list { ("first" | "subsequent" | "ibid" | "ibid-with-locator" | "near-note")+ }
        }?,
        
        ## Tests whether the item matches the given types
        attribute type {
            list { cs-types+ }
        }?,
        
        ## Tests whether the given variables contain non-empty values
        attribute variable {
            list { all-variables+ }
        }?,
        ## Specifies the test criterion (default is all)
        ##     all: a condition tests "true" when it tests "true" for all of the
        ##          given condition values
        ##     any: a condition tests "true" when it tests "true" for any of the
        ##          given condition values
        ##    none: a condition tests "true" when it tests "true" for none of the
        ##          given condition values
        attribute match { "all" | "any" | "none" }?
}

## Formatting attributes.
div {
    affixes =
        attribute prefix { text }?,
        attribute suffix { text }?
    delimiter = attribute delimiter { text }?

    ## The text of each individual cite is normally formatted as a
    ## single continuous run of text.  Portions of the cite text can be
    ## specially positioned using the display attribute.
    display = attribute display {
        
        ## Set the display value set to "block" to place the content
        ## in a block stretching from margin to margin.
        "block"
        | 
          ## Set the display value set to "left-margin" to place the
          ## content in a block of fixed width starting at the left 
          ## margin.  All "left-margin" blocks in a bibliography share
          ## the same width, set according to the maximum number of
          ## characters appearing in any one such block.
          "left-margin"
        | 
          ## Set the display value to "right-inline" to place the
          ## content in a block directly to the right of any immediately
          ## preceding "left-margin" block, and extending to the
          ## right margin.
          "right-inline"
        | 
          ## Set the display value to "indent" to block-indent the
          ## text to the right by a standard amount.
          "indent"
    }?
    
    ## attributes are drawn directly from CSS and FO where possible
    font-formatting =
        attribute font-style { "italic" | "normal" | "oblique" }?,
        attribute font-variant { "normal" | "small-caps" }?,
        attribute font-weight { "normal" | "bold" | "light" }?,
        attribute text-decoration { "none" | "underline" }?,
        attribute vertical-align { "baseline" | "sup" | "sub" }?
    
    ## When set to true (false is the default), quotes (defined as terms) are
    ## placed around the rendered text. Nested quotes flipflop.
    quotes = attribute quotes { xsd:boolean }?
    
    ## Removes any periods from the rendered text (defaults to false)
    strip-periods = attribute strip-periods { xsd:boolean }?
    
    text-case =
        attribute text-case {
            
            ## display all text as lowercase
            "lowercase"
            | 
              ## display all text as uppercase
              "uppercase"
            | 
              ## capitalize first character; other characters
              ## displayed as is
              "capitalize-first"
            | 
              ## capitalize first character of every word;
              ## other characters displayed lowercase
              "capitalize-all"
            | 
              ## display as title case (the Chicago Manual
              ## of Style calls this "headline style")
              "title"
            | 
              ## display as sentence case/sentence style
              "sentence"
        }?
}