@inproceedings{ijcai1981p89,
  title     = {An Application of AI Techniques to Structuring Objects into an Optimal Conceptual Hierarchy},
  author    = {Michalski, Ryszard S. and Stepp, Robert E.},
  booktitle = {Proceedings of the Seventh International Joint Conference on
               Artificial Intelligence, {IJCAI-81}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Roger C. Schank},
  pages     = {460--464},
  year      = {1981},
  month     = {8},
  note      = {Theoretical Foundations},
  url       = {https://ijcai.org/proceedings/1981/89},
}