Bobinaitė, Viktorija, and Aldona Juozapavičienė. “Assessment of Performance Efficiency of Enterprises Producing Electricity in Hydro and Wind Power Plants”. Business: Theory and Practice 12, no. 2 (June 22, 2011): 193-202. Accessed December 13, 2019. https://journals.vgtu.lt/index.php/BTP/article/view/8842.