Moutinho, Victor. “Is There Convergence and Causality Between the Drivers of Energy-Related Carbon Dioxide Emissions Among the Portuguese Tourism Industry?”. International Journal of Energy Economics and Policy 5, no. 3 (July 13, 2015): 828–840. Accessed May 4, 2025. https://econjournals.com.tr/index.php/ijeep/article/view/1332.