@phdthesis{oai:u-ryukyu.repo.nii.ac.jp:02007889,
 author = {Enrique, Gutierrez Carlos and エンリケ, グティエレツ　カルロス},
 month = {Mar},
 note = {学位論文},
 school = {琉球大学},
 title = {Unsupervised Classification for Main Features Extraction in Natural Disaster Text Sources},
 year = {2015}
}