@inproceedings{ijcai1981p74,
  title     = {Reasoning about Deduction with Unknown Constants},
  author    = {Eaas, Andrew},
  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     = {382--383},
  year      = {1981},
  month     = {8},
  note      = {INFERENCE and REASONING},
  url       = {https://ijcai.org/proceedings/1981/74},
}