Document Transformations and Information States Staffan Larsson author Annie Zaenen author 2000-10 text 1st SIGdial Workshop on Discourse and Dialogue Association for Computational Linguistics Hong Kong, China conference publication larsson-zaenen-2000-document 10.3115/1117736.1117749 https://aclanthology.org/W00-1013/ 2000-10 112 120