MALTESE, George. Convex Ideals and Positive Multiplicative Forms in Partially Ordered Algebras. Mathematica Scandinavica, Berkeley, CA, United States, v. 9, p. 372–382, 1961. DOI: 10.7146/math.scand.a-10642. Disponível em: https://journals.msp.org/mscand/article/view/2706. Acesso em: 25 jul. 2026.