Lenar N. Safijllin, Fathy E. Y. Abdelmajied,. «Approaches for Measuring Human Capital and Its Effect on Economic Growth in (MENA) Region: A Panel Data Analysis». Opción 34, no. 1 (junio 10, 2019): 1433-1450. Accedido agosto 3, 2025. http://www.produccioncientifica.luz.edu.ve/index.php/opcion/article/view/24185.