H`A, Huy T`ai; KEIPER, Graham; MAHMOOD, Hasan; O'ROURKE, Jonathan L. Density of $f$-ideals and $f$-ideals in mixed small degrees. Mathematica Scandinavica, Berkeley, CA, United States, v. 128, n. 1, 2022. DOI: 10.7146/math.scand.a-129244. Disponível em: https://journals.msp.org/mscand/article/view/127. Acesso em: 24 jul. 2026.