I. I. Yezhov and V. F. Kadankov, “Boundary Functionals for the Difference of Nonordinary Renewal Processes with Discrete Time”, Ukr. Mat. Zhurn., vol. 52, no. 10, pp. 1345–1356, Oct. 2000, Accessed: Apr. 09, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/4541