KUIPERS, L. Relations Between Contiguous Generalized Legendre Associated Functions (Recurrence Formulas). Mathematica Scandinavica, Berkeley, CA, United States, v. 6, p. 200–206, 1958. DOI: 10.7146/math.scand.a-10544. Disponível em: https://journals.msp.org/mscand/article/view/2798. Acesso em: 25 jul. 2026.