Anburajan, P., and A. R. S. Ramaswamy. “A Hybrid Group Acceptance Sampling Plan for Lifetimes Based on Gamma, Exponentiated Log - Logistic and Marshall - Olkin Extended Exponential Distributions”. Journal of Progressive Research in Mathematics, Vol. 2, no. 1, Feb. 2015, pp. 57-68, https://scitecresearch.com/journals/index.php/jprm/article/view/35.