Amer Jaber dr., Zahawy S. Measuring and Analysis of Productivity Efficiency by Using Cobb – Douglas Production Function in the State Company for Drug Industries in Samarras during (1986 – 2006). TANRA [Internet]. 2011 Jun. 1 [cited 2025 Sep. 8];33(103):26-45. Available from: https://tanmiyat.uomosul.edu.iq/index.php/tanmiyat/article/view/29604