B. Hecht, and D. Gergle. Proceedings of the SIGCHI Conference on Human Factors in Computing Systems (CHI '10), Atlanta, GA, USA, page 291--300. New York, ACM, (2010)
W. Gr&\#228;ther, and W. Prinz. GROUP '01: Proceedings of the 2001 International ACM SIGGROUP Conference on Supporting Group Work, page 252-259. New York, NY, USA, ACM Press, (2001)
L. Hong, E. Chi, R. Budiu, P. Pirolli, and L. Nelson. Proceedings of the Working Conference on Advanced Visual Interfaces (AVI '08), Napoli, Italy, page 65-72. (2008)