Deqing Yang Linhao Xu Wenyuan Cai Shuigeng Zhou Aoying Zhou Efficient Query Routing for XML Documents Retrieval in Unstructured Peer-to-Peer Networks. 217-223 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3007&spage=217 2004 conf/apweb/2004 APWeb db/conf/apweb/apweb2004.html#YangXCZZ04