Melnyk, L.M., and T.Yu. Gromovoy. “Desorption Mas Spectrometry Stady of Shungite”. Physics and Chemistry of Solid State 16, no. 2 (June 15, 2015): 383–387. Accessed April 27, 2024. https://journals.pnu.edu.ua/index.php/pcss/article/view/1689.