FØLNER, Erling. On groups with full Banach mean value. Mathematica Scandinavica, Berkeley, CA, United States, v. 3, p. 243–254, 1955. DOI: 10.7146/math.scand.a-10442. Disponível em: https://journals.msp.org/mscand/article/view/2881. Acesso em: 8 sep. 2026.