PONOMARYOV, S. P. On the differentiability of the functions of a segment . Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 18, n. 2, p. 135–137, 1966. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/8728. Acesso em: 7 apr. 2025.