LIU, Jianjun; CHEN, Guiyun. AN EQUIVALENT DEFINITION OF A \(\mathcal{C}\)-GROUP. Italian Journal of Pure and Applied Mathematics, [S. l.], v. 39, p. 764–760, 2018. Disponível em: https://journals.uniurb.it/index.php/ijpam/article/view/6857. Acesso em: 26 sep. 2026.