Osmanovna, Khalova Gul’nar, Isayeva Elena Andreevna, Illeritskiy Nikita Igorevich, and Smirnova Vera Alekseevna. 2019. “Issues of Natural Gas Infrastructure Development in South-Eastern Europe”. International Journal of Energy Economics and Policy 9 (6):415-20. https://econjournals.com./index.php/ijeep/article/view/8548.