Ullah, Kalim, Zawar Hussain, and Salman Arif Cheema. “Using Auxiliary Information More Efficiently in Population Variance Estimation - A New Family of Estimators”. STATISTICS, COMPUTING AND INTERDISCIPLINARY RESEARCH 2, no. 2 (December 31, 2020): 1-12. Accessed April 13, 2026. http://scir.wum.edu.pk/index.php/ojs/article/view/11.