G. P. Pelyukh, “On Global Solutions of Systems of Nonlinear Functional Differential Equations with Deviating Argument Dependent on Unknown Functions”, Ukr. Mat. Zhurn., vol. 54, no. 3, pp. 402–407, Mar. 2002, Accessed: Dec. 06, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/4076