Lotfalipour, M. R., M. A. Falahi, and M. Bastam. “Prediction of CO2 Emissions in Iran Using Grey and ARIMA Models”. International Journal of Energy Economics and Policy, vol. 3, no. 3, May 2013, pp. 229-37, https://www.econjournals.com/index.php/ijeep/article/view/475.