%0 Journal Article
%A R. V. Gamkrelidze
%T A contribution to the first variation theory
%J Doklady Akademii Nauk
%D 1965
%P 23-26
%V 161
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1965_161_1_a4/
%G ru
%F DAN_1965_161_1_a4