Pelekhata, O. B., and N. V. Reva. “Limit Theorems for the Solutions of Linear Boundary-Value Problems for Systems of Differential Equations”. Ukrains’kyi Matematychnyi Zhurnal 71, no. 7 (July 25, 2019): 930–937. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/1487.