@inproceedings{ijcai2005p133,
  title     = {Extraction of Hierarchies Based on Inclusion of Co-occurring Words with Frequency Information},
  author    = {Yamamoto, Eiko and Kanzaki, Kyoko and Isahara, Hitoshi},
  booktitle = {Proceedings of the Nineteenth International Joint Conference on
               Artificial Intelligence, {IJCAI-05}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  pages     = {1166--1173},
  year      = {2005},
  url       = {https://ijcai.org/proceedings/2005/133},
}