“…Stochastic bounds take place in various retrial models. More precisely, in the literature of queues, many researchers have undertaken to examine such a question in the same spirit, among others, we cite: Boualem [5], Boualem et al [6,7,8,9,10,11,12,13], Khalil and Falin [18], Liang [19], Liang and Kulkarni [20], Shin [25] and references therein.…”