Martingale Hardy spaces and divergence of  maximal operators associated with Walsh-Fej\’er means. Nonlinear Studies, [S. l.], v. 32, n. 1, p. 201–214, 2025. Disponível em: https://nonlinearstudies.com/index.php/nonlinear/article/view/3832. Acesso em: 20 sep. 2025.