CONNES, A.; DAELE, A. Van. The Group Property of the Invariant $S$ of von Neumann Algebras. Mathematica Scandinavica, Berkeley, CA, United States, v. 32, p. 187–192, 1973. DOI: 10.7146/math.scand.a-11454. Disponível em: https://journals.msp.org/mscand/article/view/2157. Acesso em: 25 jul. 2026.