1. Bardwell, G. F. and Crow, E. L. (1964). A two-parameter family of hyper-Poisson distributions. Journal of American Statistical Association, 59, 133–141.
2. Crow, E. L. and Bardwell, G. F. (1963). Estimation of the parameters of the hyper-Poisson distributions. In Classical and Contagious Discrete Distributions, G. P. Patil, ed. Pergamon Press, New York. Pages 127–140.
3. Gurland, J. and Tripathi, R. (1975). Estimation of parameters on some extensions of the Katz family of discrete distributions involving hypergeometric function. In Statistical Distributions in Scientific Work, Vol. I, G. P. Patil, ed. Reidel, Dordrecht-Holland. Pages 59–82.
4. Katz, L. (1963). Unified treatment of a broad class of discrete probability distributions. In Classical and Contagious Discrete Distributions, Vol. I, G. P. Patil, ed. Pergamon Press, New York. Pages 175–182.
5. Kendall, M. G. and Stuart, A. (1977). Advanced Theory of Statistics, Vol. 2, Distribution Theory ( fourth edition ). Griffin, London.