Kenneth Baclawski Mieczyslaw M. Kokar Paul A. Kogut Lewis Hart Jeffrey E. Smith William S. Holmes III Jerzy Letkowski Michael L. Aronson Extending UML to Support Ontology Engineering for the Semantic Web. 342-360 2001 conf/uml/2001 UML http://link.springer.de/link/service/series/0558/bibs/2185/21850342.htm db/conf/uml/uml2001.html#BaclawskiKKHSHLA01