N. Jindal, and B. Liu. SIGIR '06: Proceedings of the 29th annual international ACM SIGIR conference on Research and development in information retrieval, page 244--251. New York, NY, USA, ACM, (2006)
A. Esuli, and F. Sebastiani. Proceedings of EACL-06, 11th Conference of the European Chapter of the Association for Computational Linguistics, Trento, IT., (2006)
Q. Mei, X. Ling, M. Wondra, H. Su, and C. Zhai. WWW '07: Proceedings of the 16th international conference on World Wide Web, page 171--180. New York, NY, USA, ACM, (2007)
B. Liu, M. Hu, and J. Cheng. WWW '05: Proceedings of the 14th international conference on World Wide Web, page 342--351. New York, NY, USA, ACM, (2005)