1. F. Kh. Khaziev, System-Ecological Analysis of Enzymatic Activity of Soils (Moscow, 1982) [in Russian].
2. F. Kh. Khaziev, Enzymatic Activity of Soils (Moscow, 1976) [in Russian].
3. E. V. Chekotovskii, Graphical Analysis of Statistical Data in Microsoft Excel 2000 (Moscow, 2002) [in Russian].
4. I. M. Kurbatov and E. I. Dvoinishnikov, in Proceedings of Conference on Soil Enzymes (Minsk, 1968), pp. 100–107 [in Russian].
5. T. A. Shcherbakova, Enzymatic Activity of Soils and Transformation of Organic Matter (in Natural and Artificial Phytocenoses) (Minsk, 1983) [in Russian].