KWAPISZ, Jaroslaw. Quasi-symmetry without ratios. Mathematica Scandinavica, Berkeley, CA, United States, v. 125, n. 1, p. 5–12, 2019. DOI: 10.7146/math.scand.a-112190. Disponível em: https://journals.msp.org/mscand/article/view/229. Acesso em: 24 jul. 2026.