H. Zhang, M. Korayem, E. You, und D. Crandall. Proceedings of the Fifth ACM International Conference on Web Search and Data Mining, Seite 33--42. New York, NY, USA, ACM, (2012)
R. Wetzker, C. Zimmermann, C. Bauckhage, und S. Albayrak. Proceedings of the third ACM international conference on Web search and data mining, Seite 71--80. New York, NY, USA, ACM, (2010)