S.Shanmugasundaram, C.Baby. “Study Of M/M/1 Feedback Retrial Queueing Network With Three Nodes When Catastrophe Occurs”. Mathematical Statistician and Engineering Applications 71, no. 4 (September 24, 2022): 3482–3494. Accessed May 5, 2024. https://www.philstat.org/index.php/MSEA/article/view/909.