@inproceedings{ijcai2015p609,
  title     = {How to Define Certain Answers},
  author    = {Libkin, Leonid},
  booktitle = {Proceedings of the Twenty-Fourth International Joint Conference on
               Artificial Intelligence, {IJCAI-15}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Qiang Yang and Michael Wooldridge},
  pages     = {4282--4287},
  year      = {2015},
  month     = {7},
  note      = {Best Papers from Sister Conferences Track},
  url       = {https://ijcai.org/proceedings/2015/609},
}