MOTORNAYA, O. V.; MOTORNYI, V. P. On the joint approximation of a function and its derivatives in the mean. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 71, n. 2, p. 261–270, 2019. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1436. Acesso em: 5 dec. 2025.