NORMANN, D. Martin’s axiom and medial functions. MATHEMATICA SCANDINAVICA, [S. l.], v. 38, p. 167–176, 1976. DOI: 10.7146/math.scand.a-11626. Disponível em: https://www.mscand.dk/article/view/11626. Acesso em: 3 may. 2024.