Дмитриева (Dmitrieva)Е. (Elena) Д. (Dmitrievna), Леонтьева (Leontyeva)М. (Marija) М. (Mihajlovna), and Сюндюкова (Siundiukova)К. (Kristina) В. (Viktorovna), “MOLECULAR-MASS DISTRIBUTION OF HUMIC SUBSTANCES AND HYMATOMELANIC ACIDS FROM DIF-FERENT ORIGIN PEATS OF THE TULA REGION”, JCPRM, no. 4, pp. 187-194, May 2017.