Ostapenko, Olga. «SPHERES OF ENERGY EFFICIENT OPERATION OF ENERGY SUPPLY SYSTEMS WITH COGENERATION-HEAT PUMP INSTALLATIONS АND PEAK SOURCES OF HEAT IN HEAT SUPPLY SYSTEMS». Scientific Works of Vinnytsia National Technical University, no. 4 (Березень 22, 2017). дата звернення Червень 20, 2026. https://works.vntu.edu.ua/index.php/works/article/view/487.