XML with xmlns XPath

gistfile1.js

ZU.doGet('https://resolve.eidr.org/EIDR/object/10.5240/6F7E-EF59-329B-1F0A-8440-2/?type=Full&followAlias=true', 
	function(text) {
		var d = (new DOMParser()).parseFromString(text, "text/xml");
		var nsResolver = function(prefix) {  
	      var ns = {  
	        'n' : 'http://www.eidr.org/schema/1.0',  
	        'md': 'http://www.movielabs.com/md'  
	      };  
	      return ns[prefix] || null;  
	    };
	    Z.debug(ZU.xpathText(d, './/n:Language', nsResolver));
	}
);

/** THROWS ERROR
fileName => chrome://zotero/content/xpcom/utilities.js
lineNumber => 964
string => Error: NamespaceError: An attempt was made to create or change an object in a way which is incorrect with regard to namespaces
url => http://example.com
downloadAssociatedFiles => true
automaticSnapshots => true
*/