ERIKSSON, S.; RÖGER, G.; HELMERT, M. A Proof System for Unsolvable Planning Tasks. Proceedings of the International Conference on Automated Planning and Scheduling, [S. l.], v. 28, n. 1, p. 65-73, 2018. DOI: 10.1609/icaps.v28i1.13899. Disponível em: https://ojs.aaai.org/index.php/ICAPS/article/view/13899. Acesso em: 17 apr. 2024.