Syntactic Constraints on Paraphrases Extracted from Parallel Corpora Chris Callison-Burch author 2008-10 text Proceedings of the 2008 Conference on Empirical Methods in Natural Language Processing Mirella Lapata editor Hwee Tou Ng editor Association for Computational Linguistics Honolulu, Hawaii conference publication callison-burch-2008-syntactic https://aclanthology.org/D08-1021/ 2008-10 196 205