Resolving Ellipsis in Clarification Jonathan Ginzburg author Robin Cooper author 2001-07 text Proceedings of the 39th Annual Meeting of the Association for Computational Linguistics Association for Computational Linguistics Toulouse, France conference publication ginzburg-cooper-2001-resolving 10.3115/1073012.1073043 https://aclanthology.org/P01-1031/ 2001-07 236 243