MING, R. Y. C. On von Neumann regular rings - II. MATHEMATICA SCANDINAVICA, [S. l.], v. 39, p. 167–170, 1976. DOI: 10.7146/math.scand.a-11654. Disponível em: https://www.mscand.dk/article/view/11654. Acesso em: 27 apr. 2024.