Gupta R. Cost Optimization of Queueing System with Working Vacation, Setup, Feedback, Reneging, and Retention of Reneged Customers. J. Sci. Res. [Internet]. 2022 Jan. 1 [cited 2024 Nov. 21];14(1):257-68. Available from: https://banglajol.info/index.php/JSR/article/view/55075