P. Cimiano, P. Haase, and J. Heizmann. Proceedings of IUI '07: 12th International Conference on Intelligent User Interfaces, Honolulu, HI, USA, page 180-189. (2007)
R. Catizone, A. Setzer, and Y. Wilks. Proceedings of the EACL 2003 Workshop on Dialogue Systems: Interaction, Adaptation, and Styles of Management, Budapest, Hungary, (2003)
U. Callmeier, A. Eisele, U. Schäfer, and M. Siegel. Proceedings of the 4th International Conference on Language Resources and Evaluation (LREC 2004), Lisbon, Portugal, page 1205-1208. European Language Resources Association (ELRA), (2004)