"Quantile Regression Varying-Coefficient Model in The Case of Longitudinal Data: A Study on The Success Rates of Secondary Schools in Al-Diwaniyah Governorate \ Iraq" (2025) Al Kut Journal of Economics and Administrative Sciences, 17(56), ص 1097–1111. موجود في: https://kjeas.uowasit.edu.iq/index.php/kjeas/article/view/1393 (تاريخ الوصول: 5 أكتوبر 2026).