LAENENS, E.; VERMEIR, D. A universal fixpoint semantics for ordered logic. COMPUTING AND INFORMATICS, [S. l.], v. 19, n. 3, p. 221–254, 2012. Disponível em: https://www.cai.sk/ojs/index.php/cai/article/view/561. Acesso em: 24 apr. 2024.