KOTOVA, O. V.; TRIGUB, R. M. Exact order of approximation of periodic functions by one nonclassical method of summation of Fourier series. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 64, n. 7, p. 954–969, 2012. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2631. Acesso em: 5 dec. 2025.