MATTSON, Don A. Maximal $p$-Systems and Realcompleteness. Mathematica Scandinavica, Berkeley, CA, United States, v. 35, p. 215–222, 1974. DOI: 10.7146/math.scand.a-11548. Disponível em: https://journals.msp.org/mscand/article/view/2095. Acesso em: 25 jul. 2026.