KOLBERG, O. Congruences for the Coefficients of the Modular Invariant $j(\tau)$. Mathematica Scandinavica, Berkeley, CA, United States, v. 10, p. 173–181, 1962. DOI: 10.7146/math.scand.a-10525. Disponível em: https://journals.msp.org/mscand/article/view/2669. Acesso em: 25 jul. 2026.