Saienko, Y. L., and D. M. Kaliuzhnyi. “The Generalized Mathematical Model of Factual Contribution Distribution in Voltage Symmetry Distortion and Voltage Deviation at the Point of Common Coupling”. Visnyk of Vinnytsia Politechnical Institute, no. 6, Dec. 2017, pp. 80-85, https://visnyk.vntu.edu.ua/index.php/visnyk/article/view/2149.