Ostapenko, Olga. 2017. «SPHERES OF HIGH ENERGY EFFICIENCY OF ENERGY SUPPLY SYSTEMS WITH COGENERATION-HEAT PUMP INSTALLATIONS OF SMALL POWER АND FUEL-FIRED BOILERS IN HEAT SUPPLY SYSTEMS». Scientific Works of Vinnytsia National Technical University, вип. 1 (Липень):1-8. https://works.vntu.edu.ua/index.php/works/article/view/497.