@inproceedings{ijcai1985p197,
  title     = {Optical Navigation by the Method of Differences},
  author    = {Lucas, Bruce D. and Kanade, Takeo},
  booktitle = {Proceedings of the Ninth International Joint Conference on
               Artificial Intelligence, {IJCAI-85}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Aravind Joshi},
  pages     = {951--953},
  year      = {1985},
  note      = {Perception},
  url       = {https://ijcai.org/proceedings/1985/197},
}