ZADEREI, P. V.; SMAL, ' B. A. On the Convergence of Fourier Series in the Space $L_1$. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 54, n. 5, p. 639–646, 2002. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4102. Acesso em: 6 dec. 2025.