S. Decker, M. Erdmann, D. Fensel, и R. Studer. Database Semantics, Semantic Issues in Multimedia Systems, стр. 351--369. Kluwer Academic Publisher, Boston, (1999)
D. Fensel, S. Decker, M. Erdmann, и R. Studer. Proceedings of the 11th International Flairs Conference (FLAIRS-98), Sanibel Island, Florida, (мая 1998)