%0 Journal Article
%A Harry A.W.M. Kneppers
%T Two-dimensional formal groups: from isomorphism to isogeny.
%J Mathematische Zeitschrift
%D 1990
%P 309-314
%V 205
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MZ_1990__205_3_174176/
%F MZ_1990__205_3_174176