1. Great Russian Encyclopedia. The Earth (Russian Encyclopedia, Moscow, 2004–2017) [in Russian].
2. G. A. Zilov, Chemistry of Environment (Irkutsk Gos. Univ., Irkutsk, 2006) [in Russian].
3. N. F. Pivovarova, Biosphere and People: A Handbook (Novosibirsk Gos. Ped. Univ., Novosibirsk, 1998) [in Russian].
4. T. B. Coplien, “Reporting of stable hydrogen, carbon and oxygen isotopic abundances (technical report),” Pure Appl. Chem.66 (2), 273 (1994).
5. D. C. Coleman and B. Fry, Carbon Isotope Techniques (Academic Press, San Diego, 1991), p. 158.