Christian Morbidoni Axel Polleres Giovanni Tummarello Who the FOAF knows Alice? A Needed Step Toward Semantic Web Pipes. 2007 New Forms of Reasoning for the Semantic Web http://www.ceur-ws.org/Vol-291/paper04.pdf conf/semweb/2007nfrsw db/conf/semweb/nfrsw2007.html#MorbidoniPT07