Analyzing the Two-Phase Heterogeneous and Batch Service Queuing System with Breakdown in Two-Phases, Feedback, and Vacation. Baghdad Sci.J [Internet]. 2024 Aug. 1 [cited 2025 Jan. 24];21(8):2701. Available from: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/9126