Khan, Aamir, and Himayatullah Khan. “Return to Education and Endogeneity Bias: A Study Of Higher Education Institutions in Khyber Pakhtunkhwa, Pakistan”. Pakistan Journal of Social Sciences 40, no. 2 (June 30, 2020): 603-614. Accessed February 14, 2026. https://pjss.bzu.edu.pk/index.php/pjss/article/view/869.