%0 Journal Article
%A Chrastina, Jan
%T On formal theory of differential equations. III.
%J Mathematica Bohemica
%D 1991
%P 60-90
%V 116
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.21136/MB.1991.126196/
%R 10.21136/MB.1991.126196
%G en
%F 10_21136_MB_1991_126196