Talpur, M. G. . H., A. Fazlani, S. A. N. S. Hussani, and R. M. Ilyas. “RENEWAL PROCESS OF PH-DISTRIBUTIONS WITH DUAL PROBLEM”. Biological Sciences - PJSIR, vol. 45, no. 3, Apr. 2002, pp. 165-7, https://v2.pjsir.org/index.php/biological-sciences/article/view/1778.