JONDRUP, S.; SMALL, L. W. Power Series over Coherent Rings. MATHEMATICA SCANDINAVICA, [S. l.], v. 35, p. 21–24, 1974. DOI: 10.7146/math.scand.a-11530. Disponível em: https://www.mscand.dk/article/view/11530. Acesso em: 30 apr. 2024.