DYRE, Jeppe Christoffer. Non-standard characterisations of ideals in $C(X)$. Mathematica Scandinavica, Berkeley, CA, United States, v. 50, p. 44–54, 1982. DOI: 10.7146/math.scand.a-11942. Disponível em: https://journals.msp.org/mscand/article/view/1706. Acesso em: 25 jul. 2026.