LIGUN, A. A.; SHUMEIKO, A. A. On lower bounds for the approximation of individual functions by local splines with nonfixed nodes. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 51, n. 12, p. 1628–1637, 1999. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4767. Acesso em: 27 apr. 2025.