POULSEN, E. T. On the Algebra Generated by a Continuous Function. MATHEMATICA SCANDINAVICA, [S. l.], v. 6, p. 37–39, 1958. DOI: 10.7146/math.scand.a-10533. Disponível em: https://www.mscand.dk/article/view/10533. Acesso em: 11 apr. 2025.