%0 Journal Article
%A V. I. Kazimirov
%A V. I. Plotnikov
%A I. M. Starobinets
%T An~abstract scheme for the method of variations and necessary conditions for an extremum
%J Izvestiya. Mathematics 
%D 1986
%P 133-151
%V 26
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM2_1986_26_1_a4/
%G en
%F IM2_1986_26_1_a4