S. Bloehdorn, and A. Hotho. Proceedings of the MSW 2004 workshop at the 10th ACM SIGKDD Conference on Knowledge Discovery and Data Mining, page 70-87. (August 2004)
M. Ciaramita, T. Hofmann, and M. Johnson. IJCAI-03, Proceedings of the Eighteenth International Joint Conference on Artificial Intelligence, Acapulco, Mexico, August 9-15, 2003, page 817-822. Morgan Kaufmann, (2003)
P. Eklund, and P. Deer. Proceedings of the 9th Int. Conf. on Information Processing and Management of Uncertainty (IPMU 2002), page 187-194. ESIA - Universite Savoie, (2002)presentation slides.