M. Becker, J. Mueller, A. Hotho, and G. Stumme. 1st International Workshop on Pervasive Urban Crowdsensing Architecture and Applications, PUCAA 2013, Zurich, Switzerland -- September 9, 2013. Proceedings, page New York, NY, USA. ACM, (2013)Accepted for publication.
J. Freyne, S. Anand, I. Guy, and A. Hotho. Proceedings of the fifth ACM conference on Recommender systems, page 383--384. New York, NY, USA, ACM, (2011)