A. Schein, A. Popescul, L. Ungar, и D. Pennock. SIGIR '02: Proceedings of the 25th annual international ACM SIGIR conference on Research and development in information retrieval, стр. 253--260. New York, NY, USA, ACM Press, (2002)
J. Gama, и G. Castillo. Advances in Artificial Intelligence - IBERAMIA 2002: 8th Ibero-American Conference on AI, Seville, Spain, November 12-15, 2002. Proceedings, (2002)