Skrzypek , Jurand. “Energy and Emissions Intensity Analysis of Sectors of the Polish Economy in the Years 1996-2015”. Studia Oeconomica Posnaniensia 6, no. 9 (September 30, 2018): 78–103. Accessed September 3, 2026. https://journals.ue.poznan.pl/soep/article/view/3830.