CHRISTENSEN, Erik. Non Commutative Integration for Monotone Sequentially Closed $C^*$ Algebras. Mathematica Scandinavica, Berkeley, CA, United States, v. 31, p. 171–190, 1972. DOI: 10.7146/math.scand.a-11423. Disponível em: https://journals.msp.org/mscand/article/view/2221. Acesso em: 25 jul. 2026.