Ossia

gistfile1.ly

\version "2.19.20"

\score {
    \relative c''
    \new StaffGroup 
    \with {
        \remove "System_start_delimiter_engraver"
        \override SpanBar.glyph-name = #"!" 
    } 
    <<
    \new Staff = "violin" { 
        \key d \major
        c1 c1
        <<
            { c1 c1 } 
            \new Staff 
            \with {
                alignAboveContext = #"violin"
                \remove "Time_signature_engraver"
                fontSize = #-2
                \override StaffSymbol.staff-space = #(magstep -2)  
            } 
            { 
                \key d \major 
                c,4^"Piano" es f fis g1 
            }
        >>
        c1 c1 
    }
    >>
}