TKACZYK, M. On axiomatization of Łukasiewicz’s four-valued modal logic. Logic and Logical Philosophy, [S. l.], v. 20, n. 3, p. 215–232, 2011. DOI: 10.12775/LLP.2011.012. Disponível em: https://apcz.umk.pl/LLP/article/view/LLP.2011.012. Acesso em: 16 aug. 2024.