H. Bunt, M. Kipp, M. Maybury, and W. Wahlster. Multimodal Intelligent Information Presentation, volume 27 of Text, Speech and Language Technology, Springer, Dordrecht, (2005)
R. op den Akker, H. Bunt, S. Keizer, and B. van Schooten. Proceedings of Interspeech 2005---Eurospeech: 9th European Conference on Speech Communication and Technology. Lisbon, Portugal, page 2793--2796. (2005)
S. Rosset, O. Galibert, G. Illouz, and A. Max. Proceedings of Interspeech 2006---ICSLP: 9th International Conference on Spoken Language Processing, Pittsburgh, PA, USA, page 1914-1917. (2006)
H. Pon-Barry, F. Weng, and S. Varges. Proceedings of Interspeech 2006---ICSLP: 9th International Conference on Spoken Language Processing, Pittsburgh, PA, USA, page 1930-1933. (2006)