E. Schwarzkopf, M. Bauer, and D. Dengler. Proceedings of the 8th international conference on Intelligent user interfaces, page 287--289. New York, NY, USA, ACM, (2003)
E. Schwarzkopf, M. Bauer, and D. Dengler. Proceedings of the 7th international conference on Intelligent user interfaces, page 220--221. New York, NY, USA, ACM, (2002)
S. Rodriguez, N. Gaud, and S. Galland. the 2014 IEEE/WIC/ACM International Conference on Intelligent Agent Technology, Warsaw, Poland, IEEE Computer Society Press, (2014)