"Measuring the Degree of the Effect of the Financial and Operating Leverages on the Earning per Share in the Energy Companies" (2025) مجلة اقتصاديات شمال افريقيا, 19(32), ص 91–110. موجود في: https://journals.univ-chlef.dz/index.php/renaf/article/view/522 (تاريخ الوصول: 22 أكتوبر 2026).