For citations:

Ostrovscaya E.V., Brekhovskikh V.F., Volkova Z.V., Monakhov S.K., Kurapov A.A., Kocharan A.G. Heavy metals in system «Delta of Volga - Northern Caspian Sea. South of Russia: ecology, development. 2008;3(4):156-163. (In Russ.) https://doi.org/10.18470/1992-1098-2008-4-156-163