S. White, and P. Smyth. Proceedings of the Ninth ACM SIGKDD International Conference on Knowledge Discovery and Data Mining, page 266--275. New York, NY, USA, ACM, (2003)
W. Hwang, T. Kim, M. Ramanathan, and A. Zhang. Proceeding of the 14th ACM SIGKDD international conference on Knowledge discovery and data mining, page 336--344. New York, NY, USA, ACM, (2008)