BÜYÜKASIK, Engin; LOMP, Christian. Rings whose modules are weakly supplemented are perfect. Applications to certain ring extensions. Mathematica Scandinavica, Berkeley, CA, United States, v. 105, n. 1, p. 25–30, 2009. DOI: 10.7146/math.scand.a-15104. Disponível em: https://journals.msp.org/mscand/article/view/593. Acesso em: 24 jul. 2026.