Kupczyk, Adam. “Production of Liquid Transportation Biofuel in Poland in Terms of UE Conditions. Present State and Prospects”. Zeszyty Naukowe SGGW - Ekonomika i Organizacja Gospodarki Żywnościowej, no. 57 (December 17, 2005): 35–44. Accessed April 3, 2025. https://eiogz.sggw.edu.pl/article/view/9678.