1. Agrochemical Methods of Soil Examination (Nauka, Moscow, 1975) [in Russian].
2. V. V. Kanev, Gleyzation and Podzolization Parameters in Soils on Mantle Loams in the Northeastern Russian Plain (Ross. Akad. Nauk, Yekaterinburg, 2001) [in Russian].
3. B. A. Nikitin, “Specification of Procedure for the Determination of Humus in Soil,” Agrokhimiya, No. 8, 18–26 (1983).
4. PNDF 14.1:2:4.190-03: Procedure of Determining Dichromate Oxidation Rate in Samples of Natural, Potable, and Waste Waters by Photometry Using the Fluorate-02 Liquid Analyzer (Moscow, 2003) [in Russian].