%0 Journal Article
%A Z. Kowalski
%T Generalized characteristic directions for a system of differential equations
%J Annales Polonici Mathematici
%D 1959
%P 269-280
%V 6
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.4064/ap-6-3-269-280/
%R 10.4064/ap-6-3-269-280
%G en
%F 10_4064_ap_6_3_269_280