Bratiichuk MS, Chechelnitsky AA, Usar IY. M/M/1 retrial queueing model with variable service rate. Ukr. Mat. Zhurn. [Internet]. 2020Mar.28 [cited 2024Apr.20];72(3):355-6. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/813