LOMAKINA, E. N. On Estimates of the Approximation Numbers of the Hardy Operator. Eurasian Mathematical Journal, [S. l.], v. 6, n. 2, p. 41–62, 2015. Disponível em: https://emj.enu.kz/index.php/main/article/view/607. Acesso em: 31 oct. 2025.