Existence of bounded solutions of nonlinear difference equations in a Banach space. Neliniini Kolyvannya, [S. l.], v. 16, n. 2, p. 165–172, 2013. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/690. Acesso em: 21 jan. 2026.