@inproceedings{ijcai1985p90,
  title     = {Two Results on Default Logic},
  author    = {Lukaszewicz, Witold},
  booktitle = {Proceedings of the Ninth International Joint Conference on
               Artificial Intelligence, {IJCAI-85}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Aravind Joshi},
  pages     = {459--460},
  year      = {1985},
  note      = {Knowledge Representation},
  url       = {https://ijcai.org/proceedings/1985/90},
}