Kirichenko, Olga S., Alexey A. Komzolov, Yulia A. Nazarova, Natalya S. Shcherbakova, and Tatiana V. Kirichenko. 2020. “Diversification of Russian Oil and Gas Upstream Companies”. International Journal of Energy Economics and Policy 10 (3):112-18. https://econjournals.com/index.php/ijeep/article/view/9194.