D. Ramage, P. Heymann, C. Manning, and H. Molina. Proceedings of the Second ACM International Conference on Web Search and Data Mining, page 54--63. New York, NY, USA, ACM, (2009)
C. Brooks, and N. Montanez. WWW '06: Proceedings of the 15th international conference on World Wide Web, page 625--632. New York, NY, USA, ACM Press, (2006)
C. Brooks, and N. Montanez. WWW ’06: Proceedings of the 15th international conference on World Wide Web, page 625--632. New York, NY, USA, ACM Press, (2006)