DAVISON, T. M. D’Alembert’s functional equation and Chebyshev polynomials. Annales Universitatis Paedagogicae Cracoviensis Studia Mathematica, [S. l.], v. 1, p. 31–38, 2001. Disponível em: https://studmath.uken.krakow.pl/article/view/13514. Acesso em: 30 oct. 2026.