Professor Leonid Yu. Kossovich (to the 70$^{\mathrm {th}}$ anniversary)

The present paper is devoted to the 70th Anniversary of the Editor-in-Chief of “Izvestiya of Saratov University. New Series. Series: Mathematics. Mechanics. Informatics”, DSc (Physics & Mathematics), Prof., Head of the Department of Mathematical Theory of Elasticity and Biomechanics, a Laureate of the State Prize of the Russian Federation in the field of science and technology Leonid Yu. Kossovich.