M. Liu, R. Cai, M. Zhang, и L. Zhang. Proceedings of the 20th ACM international conference on Information and knowledge management, стр. 87--92. New York, NY, USA, ACM, (2011)
X. Bai, B. Cambazoglu, и F. Junqueira. Proceedings of the 20th ACM international conference on Information and knowledge management, стр. 77--86. New York, NY, USA, ACM, (2011)