Pryszcz, Adrian, Barbora Grycová, Ivan Koutník, and Veronika Blahůšková. “Characterization of Tar Deposits, Extraction and Sorption Properties”. GeoScience Engineering 62, no. 2 (June 30, 2016): 1–4. Accessed May 3, 2024. http://www.geoscience.cz/ojs/index.php/GSE/article/view/105.