S. Charfi, E. Dubois, and R. Bastide. Task Models and Diagrams for User Interface Design, volume 4849 of Lecture Notes in Computer Science, Springer Berlin Heidelberg, (2007)
M. Haouach, G. Venturini, and C. Guinot. HT '09: Proceedings of the Twentieth ACM Conference on Hypertext and Hypermedia, New York, NY, USA, ACM, (July 2009)