T. Leong, F. Vetere, and S. Howard. Proceedings of 19th conference of the computer-human interaction
special interest group, page 1-4. Narrabundah, Australia, (2005)
K. Hoashi, K. Matsumoto, and N. Inoue. Proceedings of eleventh ACM international conference
on Multimedia, page 110-119. New York, NY, USA, ACM Press, (2003)