@inproceedings{ijcai2009p118,
  title     = {Extending Decidable Cases for Rules with Existential Variables},
  author    = {Baget, Jean-François and Leclère, Michel and Mugnier, Marie-Laure and Salvat, Eric},
  booktitle = {Proceedings of the Twenty-First International Joint Conference on
               Artificial Intelligence, {IJCAI-09}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Hiroaki Kitano},
  pages     = {677--681},
  year      = {2009},
  url       = {https://ijcai.org/proceedings/2009/118},
}