Patel, I. D., and A. V. Gajjar. “Life Test Based on Progressively Group-Censored Samples From Exponential Distribution With Periodic Change in Failure Rate”. Defence Science Journal 29, no. 4 (February 25, 2014): 167–172. Accessed July 8, 2025. https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/6517.