BUSHEV, D. M. Approximation of classes of convolutions by linear methods of summation of Fourier series. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 49, n. 6, p. 739–753, 1997. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5059. Acesso em: 5 dec. 2025.