G. Webb, S. Butler, and D. Newlands. Proceedings of The Ninth ACM SIGKDD International Conference on Knowledge Discovery and Data Mining (KDD-2003), page 256-265. New York, The Association for Computing Machinery, (2003)
G. Webb. Proceedings of the Twelfth ACM SIGKDD International Conference on Knowledge Discovery and Data Mining (KDD-2006), page 434 - 443. New York, The Association for Computing Machinery, (2006)