Shan Gao and  Zaiming Liu,  Performance Analysis of a Discrete-time GeoX/G/1 Queue with Single Working Vacation.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    August 2011, vol. 56(8). 1232 - 1240
    [viewed 19 January 2020]. Available from: https://publications.waset.org/pdf/12986.