E. Agirre, E. Alfonseca, K. Hall, J. Kravalova, M. Pasca, and A. Soroa. Proceedings of Human Language Technologies: The 2009 Annual Conference of the North American Chapter of the Association for Computational Linguistics, page 19--27. Stroudsburg, PA, USA, Association for Computational Linguistics, (2009)
G. Ifrim, M. Theobald, and G. Weikum. Proceedings of the 22nd International Conference on Machine Learning - Learning in Web Search (LWS 2005), page 18--26. Bonn, Germany, (2005)