F. Radeke, und P. Forbrig. Proceedings of the 6th international conference on Task models and diagrams for user interface design, Seite 184--197. Berlin/Heidelberg, Springer-Verlag, (2007)
A. Neto, und R. de Mattos Fortes. Proceedings of the 28th ACM International Conference on Design of Communication, Seite 151--158. New York, NY, USA, ACM, (2010)