@InProceedings{voorhees:2008:ACLMain, author = {Voorhees, Ellen M.}, title = {Contradictions and Justifications: Extensions to the Textual Entailment Task}, booktitle = {Proceedings of ACL-08: HLT}, month = {June}, year = {2008}, address = {Columbus, Ohio}, publisher = {Association for Computational Linguistics}, pages = {63--71}, url = {http://www.aclweb.org/anthology/P/P08/P08-1008} }