RANKIN, R. A. Chebyshev polynomials and the modulary group of level p. MATHEMATICA SCANDINAVICA, [S. l.], v. 2, p. 314–325, 1954. DOI: 10.7146/math.scand.a-10417. Disponível em: https://www.mscand.dk/article/view/10417. Acesso em: 19 may. 2024.