aboud, bader, and Mustafa Ismaeel Naif. “The Performance of Some Restricted Estimators In Restricted Linear Regression Model”. Al-Qadisiyah Journal of Pure Science 26, no. 2 (April 16, 2021): Math. 86-. Accessed May 3, 2024. https://journalsc.qu.edu.iq/index.php/JOPS/article/view/1287.