G. Schmiedl, M. Seidl, and K. Temper. Proceedings of the 11th International Conference on Human-Computer Interaction with Mobile Devices and Services, page 1--2. Bonn, Germany, ACM, (2009)
S. Günnemann, I. Färber, and T. Seidl. Proceedings of the 18th ACM SIGKDD international conference on Knowledge discovery and data mining, page 132--140. New York, NY, USA, ACM, (2012)