Surender Kumar, Pooja Bhatia, and Neelam. 2024. “Numerical And Graphical Study Of The Average Queue Length For A Hierarchical Feedback Queuing System With Four Servers And The Limited Number Of Revisits To Any One Server”. Revista Electronica De Veterinaria 25 (2), 1382-93. https://doi.org/10.69980/redvet.v25i2.1812.