%0 Journal Article
%A P. V. Al'brecht
%T Differentiable operators of nearly best approximation
%J Izvestiya. Mathematics 
%D 1999
%P 631-647
%V 63
%N 4
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM2_1999_63_4_a0/
%G en
%F IM2_1999_63_4_a0