Życzyńska, Anna, and Tomasz Cholewa. “The Modifications to the Requirements on Energy Savings and Thermal Insulation of Buildings in Poland in the Years 1974-2021”. Budownictwo i Architektura 14, no. 1 (March 10, 2015): 145–154. Accessed May 15, 2024. https://ph.pollub.pl/index.php/bia/article/view/1680.