Ambya, Ambya, Toto Gunarto, Ernie Hendrawaty, Fajrin Satria Dwi Kesumah, and Febryan Kusuma Wisnu. 2020. “Future Natural Gas Price Forecasting Model and Its Policy Implication”. International Journal of Energy Economics and Policy 10 (5):64-70. https://econjournals.com.tr/index.php/ijeep/article/view/9676.