%0 Journal Article
%A V. D. Budaev
%T On the Bessel inequality for systems of root functions of
%J Doklady Akademii Nauk
%D 1991
%P 16-20
%V 318
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1991_318_1_a1/
%G ru
%F DAN_1991_318_1_a1