@inproceedings{ijcai2001p179,
  title     = {A Hierarchy of Boundary-based Shape Descriptors},
  author    = {Meathrel, Richard C. and Galton, Antony},
  booktitle = {Proceedings of the Seventeenth International Joint Conference on
               Artificial Intelligence, {IJCAI-01}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  pages     = {1359--1363},
  year      = {2001},
  url       = {https://ijcai.org/proceedings/2001/179},
}