DYUZHENKOVA, O. Yu. A remark concerning the modulus of smoothness introduced by Ditzian and Totik. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 47, n. 12, p. 1627–1638, 1995. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5556. Acesso em: 5 dec. 2025.