NIKOLOV, G. ON TURAN’S INEQUALITY FOR ULTRASPHERICAL POLYNOMIALS. Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 101, p. 105–114, 2013. Disponível em: https://annual.uni-sofia.bg/index.php/fmi/article/view/233. Acesso em: 9 apr. 2025.