D. Traum, and S. Larsson. Current and New Directions in Discourse and Dialogue, volume 22 of Text, Speech and Language Technology, Springer Netherlands, (2003)
R. Schaefer, S. Bleul, and W. Mueller. Engineering Human Computer Interaction and Interactive Systems, volume 3425 of Lecture Notes in Computer Science, Springer Berlin Heidelberg, (2005)
S. Römer, J. Mayer, F. Schweiggert, M. Maier, and T. Vollmer. Proceedings of the 25th conference on IASTED International Multi-Conference: Software Engineering, page 183--191. Anaheim, CA, USA, ACTA Press, (2007)
J. Van den Bergh, and K. Coninx. Proceedings of the 6th international conference on Task models and diagrams for user interface design, page 98--111. Berlin/Heidelberg, Springer-Verlag, (2007)
R. Schaefer, S. Bleul, and W. Mueller. Task Models and Diagrams for Users Interface Design, volume 4385 of Lecture Notes in Computer Science, chapter 4, Springer-Verlag, Berlin/Heidelberg, (2007)