%0 Journal Article
%A S. N. Vasil'ev
%T Widths of some functional classes in the space $L_2$ on a period
%J Trudy Instituta matematiki i mehaniki
%D 2013
%P 42-47
%V 19
%N 4
%I mathdoc
%U http://geodesic.mathdoc.fr/item/TIMM_2013_19_4_a4/
%G ru
%F TIMM_2013_19_4_a4