HYLLERAAS, Egil A. Linearization of Products of Jacobi Polynomials. MATHEMATICA SCANDINAVICA, [S. l.], v. 10, p. 189–200, 1962. DOI: 10.7146/math.scand.a-10527. Disponível em: https://tidsskrift.dk/math/article/view/10527. Acesso em: 14 aug. 2026.