Nitika, Nitika, Sidharth Sekhar Mishra, and Pallavi Lohani. “Lexis Expansion: A Prerequisite for Analyzing Time Changing Variables in a Cohort Study”. Nepal Journal of Epidemiology 7, no. 2 (August 8, 2017): 681–684. Accessed April 19, 2024. https://www.nepjol.info/index.php/NJE/article/view/17974.