S. Kamvar, T. Haveliwala, C. Manning, и G. Golub. WWW '03: Proceedings of the 12th international conference on World Wide Web, стр. 261--270. New York, NY, USA, ACM Press, (2003)
S. White, и P. Smyth. KDD '03: Proceedings of the ninth ACM SIGKDD international conference on Knowledge discovery and data mining, стр. 266--275. New York, NY, USA, ACM Press, (2003)