Zhiznin, S. Z., V. M. Timohov, and V. Dineva. “Energy Security: Theoretical Interpretations and Quantitative Evaluation”. International Journal of Energy Economics and Policy, vol. 10, no. 2, Jan. 2020, pp. 390-0, https://www.econjournals.com/index.php/ijeep/article/view/8950.