Samoilenko, A.M. and Teplinsky, Y.V. (1995) “On the reducibility of countable systems of linear difference equations”, Ukrains’kyi Matematychnyi Zhurnal, 47(11), pp. 1533–1541. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/5544 (Accessed: 14 April 2025).