STENSTRÖM, B. The Maximal Ring of Quotients of a Triangular Matrix Ring. MATHEMATICA SCANDINAVICA, [S. l.], v. 34, p. 162–166, 1974. DOI: 10.7146/math.scand.a-11517. Disponível em: https://www.mscand.dk/article/view/11517. Acesso em: 3 may. 2024.