J. Moskaliuk, J. Kimmerle, und U. Cress. Proceedings of the International Conference of the Learning Sciences 2008(Bd. 2, S. 99-106). Utrecht, The Netherlands: International Society of the Learning Sciences, Seite 99-106. (2008)
P. Pirolli, E. Wollny, und B. Suh. CHI '09: Proceedings of the 27th international conference on Human factors in computing systems, ACM, New York, NY, USA, (2009)