Contradictions and Justifications: Extensions to the Textual Entailment Task Ellen M Voorhees author 2008-06 text Proceedings of ACL-08: HLT Johanna D Moore editor Simone Teufel editor James Allan editor Sadaoki Furui editor Association for Computational Linguistics Columbus, Ohio conference publication voorhees-2008-contradictions https://aclanthology.org/P08-1008/ 2008-06 63 71