Kolesnikov, S. I.; Moshchenko, D. I.; Kuzina, A. A.; Kazeev, K. S.; Akimenko, Y. V. Development of Regional Maximum Permissible Concentrations of Oil, Lead, Chromium, Nickel, and Copper in the Ordinary Black Soils of Central Ciscaucasia. AmazInv 2019, 8, 38-44.