Borek, Kinga, and Wacław Romaniuk. “Biogas Installations for Harvesting Energy and Utilization of Natural Fertilisers”. Agricultural Engineering 24, no. 1 (March 30, 2020): 1-14. Accessed December 4, 2024. http://agriceng.ptir.org/index.php/AgricEng/article/view/211.