C. Schmitz, A. Hotho, R. Jäschke, and G. Stumme. Data Science and Classification. Proceedings of the 10th IFCS Conf., page 261--270. Heidelberg, Springer, (July 2006)
T. Rattenbury, N. Good, and M. Naaman. SIGIR '07: Proceedings of the 30th Annual International ACM SIGIR Conference on Research and Development in Information Retrieval, page 103--110. New York, NY, USA, ACM Press, (2007)
C. Cattuto, D. Benz, A. Hotho, and G. Stumme. The Semantic Web -- ISWC 2008, Proc.Intl. Semantic Web Conference 2008, volume 5318 of LNAI, page 615--631. Heidelberg, Springer, (2008)
L. Wu, X. Hua, N. Yu, W. Ma, and S. Li. MM '08: Proceeding of the 16th ACM international conference on Multimedia, page 31--40. New York, NY, USA, ACM, (2008)