ALFSEN, Erik M.; HOLM, Per. A Note in Compact Representations and Almost Periodicity in Topological Groups. Mathematica Scandinavica, Berkeley, CA, United States, v. 10, p. 127–136, 1962. DOI: 10.7146/math.scand.a-10519. Disponível em: https://journals.msp.org/mscand/article/view/2664. Acesso em: 25 jul. 2026.