Nagy, Gábor. “Submerged Aquatic Plant (Vallisneria Spiralis and Egeria Densa) Utilisation As a Biogas Cleaner and Feedstock of Co-Digestion”. International Journal of Engineering and Management Sciences, vol. 4, no. 4, Dec. 2019, pp. 172-80, https://doi.org/10.21791/IJEMS.2019.4.19.