%0 Journal Article
%A T. V. Elina
%T The best approximation of convolution-type operator on the class of doubly differentiable functions
%J Trudy Instituta matematiki i mehaniki
%D 1992
%P 70-78
%V 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/TIMM_1992_2_a6/
%G ru
%F TIMM_1992_2_a6