%0 Journal Article
%A S. B. Vakarchuk
%A V. I. Zabutnaya
%T A Sharp Inequality of Jackson--Stechkin type in~$L_2$ and the Widths of Functional Classes
%J Matematičeskie zametki
%D 2009
%P 328-336
%V 86
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MZM_2009_86_3_a1/
%G ru
%F MZM_2009_86_3_a1