Diego Calvanese Elio Damaggio Giuseppe De Giacomo Maurizio Lenzerini Riccardo Rosati Semantic Data Integration in P2P Systems. 77-90 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2944&spage=77 2003 conf/dbisp2p/2003 DBISP2P db/conf/dbisp2p/dbisp2p2003.html#CalvaneseDGLR03