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2. K. S. Bobkova, A. V. Mashika, and A. V. Smagin, Dynamics of the Content of Organic Carbon in Automorphic Soils of Middle-Taiga Spruce Forests (Nauka, St. Petersburg, 2014) [in Russian].
3. M. M. Kononova, Problem of Soil Humus and Modern Challenges of Its Study (Academy of Sciences of the Soviet Union, Moscow, 1951) [in Russian].
4. E. Yu. Milanovskii, Soil Humus Substances as the Natural Hydrophobic-Hydrophilic Compounds (GEOS, Moscow, 2009) [in Russian].
5. M. A. Nadporozhskaya, L. B. L’vova, N. V. Kovsh, E. I. Fedoros, and O. G. Chertov, “Influence of lithogenic factor on the transformation of nitrogen compounds in forest soils,” Proceedings of the V All-Russian Conf. with International Participation on Forest Soil Science “Diversity of Forest Soils and Biological Diversity of Forests (Pushchino, 2013), pp. 84–86