T. Joachims. Proceedings of ICML-99, 16th International Conference on Machine Learning, page 200--209. Bled, SL, Morgan Kaufmann Publishers, San Francisco, US, (1999)
H. Yu, J. Han, and K. Chang. KDD '02: Proceedings of the eighth ACM SIGKDD international conference on Knowledge discovery and data mining, page 239--248. New York, NY, USA, ACM Press, (2002)