DZYUBENKO, H. A. Almost coconvex approximation of continuous periodic functions. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 71, n. 3, p. 353–367, 2019. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/1444. Acesso em: 27 apr. 2025.