SCHREYE, D. De. Integrable-ergodic $C^*$-dynamical systems on Abelian groups. Mathematica Scandinavica, Berkeley, CA, United States, v. 57, p. 189–205, 1985. DOI: 10.7146/math.scand.a-12111. Disponível em: https://journals.msp.org/mscand/article/view/1556. Acesso em: 25 jul. 2026.