ENAYATI, F.; ASGARI, M. S. On the Generalized Riesz-Dual Sequences in Hilbert Spaces. Eurasian Mathematical Journal, [S. l.], v. 8, n. 4, p. 45–54, 2017. Disponível em: https://emj.enu.kz/index.php/main/article/view/679. Acesso em: 7 jan. 2026.