عبد الحميد م.م. and عبد اللطيف م.ح. (2018) “(Estimation and Analysis of the Cobb-Duglas Production Function for the Rail Transport Sector in Iraq for the Period 1990-2016 using the ARDL Model)”, Journal of Economics and Administrative Sciences, 24(109), p. 358. doi:10.33095/jeas.v24i109.1553.