GORODNII, M. F.; DOROGOVTSEV, A. Ya. Bounded solutions of one class of nonlinear operator difference equations. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 47, n. 7, p. 890–896, 1995. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5483. Acesso em: 5 dec. 2025.