Munira M. Azimova and Nargiza M. Kurbanova (2026) “Classification of a modern heating boiler of the Saturn GPD 1535 brand ”, PROBLEMS OF ENERGY AND SOURCES SAVING, (2), pp. 63–68. Available at: https://energy.tdtu.uz/index.php/journal/article/view/186 (Accessed: 25 July 2026).