Opinion Extraction based on Syntactic Pieces Suguru Aoki author Kazuhide Yamamoto author 2007-11 text Proceedings of the 21st Pacific Asia Conference on Language, Information and Computation The Korean Society for Language and Information (KSLI) Seoul National University, Seoul, Korea conference publication aoki-yamamoto-2007-opinion http://hdl.handle.net/2065/29112 https://aclanthology.org/Y07-1007/ 2007-11 76 85