Kumar, Ashok, Vipin Kapoor, and Debabrata Ray. “On Availability of a Series System With Imperfect Detectors”. Defence Science Journal 32, no. 3 (February 17, 2014): 237-240. Accessed April 20, 2024. https://publications.drdo.gov.in/ojs/index.php/dsj/article/view/6304.