@inproceedings{ijcai1969p21,
  title     = {Concepts and Methods for Heuristic Search},
  author    = {Sandewall, Erik},
  booktitle = {Proceedings of the First International Joint Conference on
               Artificial Intelligence, {IJCAI-69}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Donald E. Walker and David C. Cooper},
  pages     = {199--218},
  year      = {1969},
  month     = {5},
  note      = {Heuristic Problem Solving},
  url       = {https://ijcai.org/proceedings/1969/21},
}