Ugli, A. R. Y., and S. S. Sirojidinovich. “The Methods for Improving the Efficiency of Flat Solar Collectors”. American Journal of Engineering , Mechanics and Architecture (2993-2637), vol. 2, no. 4, Apr. 2024, pp. 159-66, http://grnjournal.us/index.php/AJEMA/article/view/4479.