T. Hussain, S. Shamail, and M. Awais. Companion to the 19th annual ACM SIGPLAN conference on Object-oriented programming systems, languages, and applications, page 170--171. New York, NY, USA, ACM, (2004)
S. Staab, M. Erdmann, A. Mädche, and S. Decker. First Workshop on the Semantic Web at the Fourth
European Conference on Digital Libraries, Lisbon, Portugal, (September 2000)
W. Nejdl, M. Wolpers, and C. Capella. Modelle und Modellierungssprachen in Informatik und Wirtschaftsinformatik, Modellierung 2000, St. Goar, Foelbach Verlag, Koblenz, (April 2000)