STENSTRÖM, Bo. The Maximal Ring of Quotients of a Triangular Matrix Ring. Mathematica Scandinavica, Berkeley, CA, United States, v. 34, p. 162–166, 1974. DOI: 10.7146/math.scand.a-11517. Disponível em: https://journals.msp.org/mscand/article/view/2134. Acesso em: 25 jul. 2026.