@inproceedings{ijcai2003p90,
  title     = {Complexity of Determining Nonemptiness of the Core},
  author    = {Conitzer, Vincent and Sandholm, Tuomas},
  booktitle = {Proceedings of the Eighteenth International Joint Conference on
               Artificial Intelligence, {IJCAI-03}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Georg Gottlob},
  pages     = {613--617},
  year      = {2003},
  url       = {https://ijcai.org/proceedings/2003/90},
}