Polarized Unification Grammars Sylvain Kahane author 2006-07 text Proceedings of the 21st International Conference on Computational Linguistics and 44th Annual Meeting of the Association for Computational Linguistics Nicoletta Calzolari editor Claire Cardie editor Pierre Isabelle editor Association for Computational Linguistics Sydney, Australia conference publication kahane-2006-polarized 10.3115/1220175.1220193 https://aclanthology.org/P06-1018/ 2006-07 137 144