K. Kipper, H. Dang, and M. Palmer. Proceedings of the Seventeenth National Conference on Artificial Intelligence and Twelfth Conference on Innovative Applications of Artificial Intelligence, page 691--696. AAAI Press / The MIT Press, (2000)
A. Giuglea, and A. Moschitti. Proceedings of the 44th Annual Meeting of the Association for Computational Linguistics (ACL 2006). July 17-21, 2006, Sydney, Australia, Association for Computational Linguistics, Morristown, NJ, USA, (2006)