Yannis Stavrakas Kostis Pristouris Antonis Efandis Timos K. Sellis Implementing a Query Language for Context-Dependent Semistructured Data. 173-188 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3255&spage=173 2004 conf/adbis/2004 ADBIS db/conf/adbis/adbis2004.html#StavrakasPES04