Maksum, Azhar, Iskandar Muda, Arifin Lubis, and Ibnu Austrindanney Sina Azhar. 2021. “Trading of Indonesian Crude Palm Oil Supply Chain and Its Impact on Economic Growth: Implementation of Theory of Comparative Advantage and the Competitive Advantage of Nation”. International Journal of Energy Economics and Policy 11 (6):296-302. https://econjournals.com.tr/index.php/ijeep/article/view/11766.