SANDHU, G.S.; KUMAR, D. On additivity of derivations. Carpathian Mathematical Publications, [S. l.], v. 11, n. 2, p. 453–462, 2019. DOI: 10.15330/cmp.11.2.453-462. Disponível em: https://journals.pnu.edu.ua/index.php/cmp/article/view/2123. Acesso em: 26 apr. 2024.