Ostapenko, O. і Bakum, O. (2015) «ECONOMIC EFFICIENCY OF HEAT-PUMPING STATIONS ON THE CONDITIONS OF FUEL AND ENERGY RESOURCES COST CHANGE AND VARIABLE OPERATION MODES», Scientific Works of Vinnytsia National Technical University, (1). доступний у: https://works.vntu.edu.ua/index.php/works/article/view/406 (дата звернення: 27Квітень2026).