STØRMER, E. Multiplicative properties of positive maps. MATHEMATICA SCANDINAVICA, [S. l.], v. 100, n. 1, p. 184–192, 2007. DOI: 10.7146/math.scand.a-15020. Disponível em: https://www.mscand.dk/article/view/15020. Acesso em: 29 apr. 2024.