Mary F. Fernández Jérôme Siméon Building an Extensible XQuery Engine: Experiences with Galax (Extended Abstract). 1-4 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3186&spage=1 2004 conf/xsym/2004 XSym db/conf/xsym/xsym2004.html#FernandezS04