HOCHBERG, I. Ts.; ZAMBITSKY, M. K. On the theory of linear operators in spaces with two norms . Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 18, n. 1, p. 11–23, 1966. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/8649. Acesso em: 6 dec. 2025.