Smirnov, V., N. Belenok, and E. Ivanichenko. “Theoretical Fundamentals of Structural-Invariant Systems of Autonomous Objects Converting to Renewable Energy”. Vidnovluvana Energetika , no. 4 (47), Dec. 2016, pp. 20-31, https://ve.org.ua/index.php/journal/article/view/103.