PLEIJEL, Åke. On the boundary condition for the Legendre polynomials. Annales Fennici Mathematici, [S. l.], v. 2, n. 1, p. 397–408, 1976. DOI: 10.5186/aasfm.1976.0227. Disponível em: https://afm.journal.fi/article/view/134306. Acesso em: 25 nov. 2024.