Chaikovs’kyi, A. V., and O. A. Lagoda. “Bounded Solutions of a Difference Equation in Banach Space With Input Data in Subspaces”. Ukrains’kyi Matematychnyi Zhurnal 73, no. 11 (November 23, 2021): 1564 - 1575. Accessed April 20, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/6692.