BUDNIK, V. G. Coapproximation of functions convex on a disk by algebraic polynomials. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 46, n. 9, p. 1115–1122, 1994. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5628. Acesso em: 11 apr. 2025.