1. D. A. Knyazev, A. D. Fokin, and V. D. Knyazev, “The Role of Humic Substances in Formation of Ion-Conductive Soil Structures,” Pochvovedenie, No. 2, 150–157 (2002) [Eur. Soil Sci. 35 (2), 132–138 (2002)].
2. E. D. Lodygin, V. A. Beznosikov, and S. N. Chukov, “Paramagnetic Properties of Humus Acids of Podzolic and Bog-Podzolic Soils,” Pochvovedenie, No. 7, 807–810 (2007) [Eur. Soil Sci. 40 (7), 726–729 (2007)].
3. I. I. Sapezhinskii, Biopolymers: Kinetics of Radiation-Induced and Photochemical Transformations (Nauka, Moscow, 1985) [in Russian].
4. Modern Microbiology. Prokaryotes (Moscow, 2005), Vol. 1, p. 253 [in Russian].
5. Yu. I. Skurlatov and G. G. Duka, Chemistry and Life of Water (Kartya Moldavenyaske, Chisinau, 1984) [in Russian].