P. Fröhlich, M. Baldauf, S. Suette, D. Schabus, and M. Fuchs. Proceedings of the 2012 ACM annual conference on Human Factors in Computing Systems (CHI), Extended Abstracts, page 1787-1792. Austin, TX, USA, (May 2012)
S. Bhattacharyya. KDD '00: Proceedings of the sixth ACM SIGKDD
international conference on Knowledge discovery and
data mining, page 465--473. Boston, Massachusetts, United States, ACM Press, (2000)