E. Schwarzkopf, M. Bauer, и D. Dengler. Proceedings of the 8th international conference on Intelligent user interfaces, стр. 287--289. New York, NY, USA, ACM, (2003)
W. Maass, и A. Filler. Proceedings of the Workshop on Making Semantics Work For Business (MSWFB 2007), part of 1st European Semantic Technology Conference, Vienna, Austria, стр. 12-17. (2007)