Robert Meersman Karl Aberer Tharam S. Dillon Semantic Issues in E-Commerce Systems, IFIP TC2/WG2.6 Ninth Working Conference on Database Semantics, April 25-28, 2001, Hong Kong DS-9 IFIP Conference Proceedings 239 Kluwer 2003 1-4020-7351-8 db/conf/ds/ds2001.html