Nezhnikova, Ekaterina V., et al. “Investigation of the Features of Investment in the Development of Renewable Energy Sources: Main Consumers, Legal Regulation, Equipment, Rates and Delivery”. International Journal of Energy Economics and Policy, vol. 8, no. 4, July 2018, pp. 178-86, https://mail.econjournals.com/index.php/ijeep/article/view/6710.