MATTSON, D. A. Maximal $p$-Systems and Realcompleteness. MATHEMATICA SCANDINAVICA, [S. l.], v. 35, p. 215–222, 1974. DOI: 10.7146/math.scand.a-11548. Disponível em: https://www.mscand.dk/article/view/11548. Acesso em: 1 may. 2024.