عبد الحميد مناهل مصطفى, and عبد اللطيف مرتضى حسن. “(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, vol. 24, no. 109, Dec. 2018, p. 358, https://doi.org/10.33095/jeas.v24i109.1553.