A. Geven, R. Sefelin, and M. Tscheligi. Proceedings of the 8th conference on Human-computer interaction with mobile devices and services, page 157--164. Helsinki, Finland, ACM, (2006)
M. Sanderson, and B. Croft. 22nd Annual Internation ACM SIGIR Conference on Research and Development in Information Retrieval, page 206--213. Berkeley, California, United States, ACM Press, (1999)
J. Koza. Parallel Problem Solving from Nature - Proceedings of
1st Workshop, PPSN 1, volume 496 of Lecture Notes in Computer Science, page 124--128. Dortmund, Germany, Springer-Verlag, (1-3 October 1991)
G. Robertson, J. Mackinlay, and S. Card. CHI '91: Proceedings of the SIGCHI conference on Human factors in computing systems, page 189--194. New York, NY, USA, ACM, (1991)