For citations:
Sokol'skii A.F., Abdurahmanov G.M., Sokol'skaya E.A. Mathematical model of fish-productivity estimation in the Northern Caspian on the annual primary production of phytoplankton. South of Russia: ecology, development. 2009;4(4):42-43. (In Russ.) https://doi.org/10.18470/1992-1098-2009-4-42-43