%0 Journal Article
%A M. Sh. Shabozov
%A G. A. Yusupov
%T Best Polynomial Approximations in~$L_2$ of Classes of $2\pi$-Periodic Functions and Exact Values of Their Widths
%J Matematičeskie zametki
%D 2011
%P 764-775
%V 90
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MZM_2011_90_5_a10/
%G ru
%F MZM_2011_90_5_a10