%0 Journal Article
%A Ian M. Anderson
%A Juha Pohjanpelto
%T Variational principles for differential equations with symmetries and conservation laws. I. Second order scalar equations.
%J Mathematische Annalen
%D 1994
%P 191-222
%V 299
%N 4
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MAN_1994__299_4_165205/
%F MAN_1994__299_4_165205