A. Korolova, R. Motwani, S. Nabar, and Y. Xu. CIKM '08: Proceeding of the 17th ACM conference on Information and knowledge mining, page 289--298. New York, NY, USA, ACM, (2008)
N. Nejati, P. Langley, and T. Konik. ICML '06: Proceedings of the 23rd international conference on Machine learning, page 665--672. New York, NY, USA, ACM, (2006)