A new formula for the busy period of a non-empty multiserver queueing system

In a recent paper Sharma and Tarabia [Sankhya 62 (2) (2000) 273-281] obtain a density function of a busy period for an empty multichannel Markovian queue in series form. In this paper a simple approach is applied to obtain the busy period density function by taking an arbitrary number (say i) of customers present in the system initially. Also a general form for the kth order moment of the busy period distribution is given.