بشماني ش. ., and القصيري غ. . “Measuring And Analyzing The Relationship Between Gross Domestic Product And Gross Fixed Capital Formation For The Internal Trade Sector In Syria”. Tishreen University Journal- Economic and Legal Sciences Series, vol. 42, no. 4, Oct. 2020, https://journal.tishreen.edu.sy/index.php/econlaw/article/view/9955.