On M-Principally Injective and Projective S-acts. European Journal of Pure and Applied Mathematics, Maryland, USA, v. 11, n. 2, p. 431–443, 2018. DOI: 10.29020/nybg.ejpam.v11i2.3229. Disponível em: https://www.ejpam.com/index.php/ejpam/article/view/3229. Acesso em: 2 apr. 2025.