RADZIEVSKAYA, E. I.; RADZIEVSKII, G. V. On One Extremal Problem for a Seminorm on the Space $l_1$ with Weight. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 57, n. 7, p. 1002–1006, 2005. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3659. Acesso em: 5 dec. 2025.