GORODNII, M. F.; LAGODA, O. A. On Bounded Solutions of Some Classes of Two-Parameter Difference Equations in a Banach Space. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 52, n. 12, p. 1610–1614, 2000. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4565. Acesso em: 5 dec. 2025.