S. Oviatt. The Human-Computer Interaction Handbook: Fundamentals, Evolving Technologies and Emerging Applications, chapter Multimodal interfaces, L. Erlbaum Associates Inc., Hillsdale, NJ, USA, (2003)
A. Arthur, R. Lunsford, M. Wesson, and S. Oviatt. Proceedings of the 8th international conference on Multimodal interfaces, page 209--216. New York, NY, USA, ACM, (2006)
A. Neto, R. Fortes, and A. da Silva Filho. Proceedings of the 26th annual ACM international conference on Design of communication, page 277--278. New York, NY, USA, ACM, (2008)
A. Nguyen, and W. Wobcke. Proceedings of the 10th international conference on Intelligent user interfaces, page 137--144. New York, NY, USA, ACM, (2005)