CHUBARYAN, Anahit; CHUBARYAN, Armine. Definition of Strong Equality of Tautologies and Universal System for Various Propositional Logics. Armenian Journal of Mathematics, Yerevan, Armenia, v. 1, n. 2, p. pp. 30–36, 2008. Disponível em: https://armjmath.sci.am/index.php/ajm/article/view/25. Acesso em: 3 apr. 2025.