D. Millen, J. Feinberg, и B. Kerr. CHI '06: Proceedings of the SIGCHI conference on Human Factors in computing systems, стр. 111--120. New York, NY, USA, ACM Press, (2006)
H. Wu, M. Zubair, и K. Maly. HYPERTEXT '06: Proceedings of the seventeenth conference on Hypertext and hypermedia, стр. 111--114. New York, NY, USA, ACM Press, (2006)