CCOLQUE TAIPE, F. C. Characterization of relative projectives and relative injectives. Selecciones Matemáticas, [S. l.], v. 7, n. 02, p. 276-288, 2020. DOI: 10.17268/sel.mat.2020.02.10. Disponível em: https://revistas.unitru.edu.pe/index.php/SSMM/article/view/3081. Acesso em: 20 apr. 2024.