A. Maedche, and V. Zacharias. 13th European Conference on Machine Learning (ECML'02) 6th European Conference on Principles and Practice of Knowledge Discovery in Databases (PKDD'02), Helsinki, Finland, (2002)
G. Varelas, E. Voutsakis, P. Raftopoulou, E. Petrakis, and E. Milios. Proceedings of the 7th annual ACM international workshop on Web information and data management (WIDM 05), page 10--16. New York, NY, USA, ACM Press, (2005)
Z. Wu, and M. Palmer. Proceedings of the 32nd Annual Meeting of the Association for Computational Linguistics (ACL-1994), page 133--138. Las Cruces (Mexico), (1994)