M. SALIH, S.; AALI J. MOHAMMAD, A. ON -REGULAR RINGS. Journal of Education and Science (JES), [S. l.], v. 18, n. 4, p. 118–139, 2006. DOI: 10.33899/edusj.2006.77274. Disponível em: https://rjps.uomosul.edu.iq/edusj/article/view/18002. Acesso em: 4 aug. 2025.