TÜRKMEN, B. N. A generalization of semiperfect modules. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 69, n. 1, p. 104–112, 2017. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1679. Acesso em: 5 dec. 2025.