B. Choi, and Z. Yao. Foundations and Advances in Data Mining, volume 180 of Studies in Fuzziness and Soft Computing, Springer, Berlin / Heidelberg, (2005)
C. Yao, Y. Yu, S. Shou, and X. Li. WWW '08: Proceeding of the 17th international conference on World Wide Web, page 999--1008. New York, NY, USA, ACM, (2008)