1. Ya. Ya. Alekseev, “Essay on the vegetation of the Smolensk province,” in Agriculture of the Smolensk Province (1924), pp. 107–119 [in Russian].
2. GIS-Atlas “Resources of Russia” (Vseross. Nauchno-Issled. Geol. Inst. im. A. P. Karpinskogo, Moscow, 2001) [in Russian].
3. V. V. Dokuchaev, Cartography of Russian Soils (Izd. Minist. Gos. Imushchestv, 1879) [in Russian].
4. V. V. Dokuchaev, Collection of Works (Akad. Nauk SSSR, Moscow–Leningrad, 1950), Vol. 4, Part 1 [in Russian].
5. Map of Forest Inventory (Smolenskoye Poozerye National Park of Smolensk Oblast, Smolensk, 2015).