Stejskalová, Lada, Libor Ansorge, Jiří Kučera, and Elżbieta Čejka. “Role of Wastewater Treatment Plants in Pollution Reduction - Evaluated by Grey Water Footprint Indicator”. Scientific Review Engineering and Environmental Studies (SREES) 31, no. 1 (March 7, 2022): 26–36. Accessed May 18, 2022. https://srees.sggw.edu.pl/article/view/2313.