%0 Journal Article
%A D.J. Collins
%A J. Huebschmann
%T Spherical Diagrams and Indentities Among Relations.
%J Mathematische Annalen
%D 1982
%P 155-184
%V 261
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MAN_1982__261_182872/
%F MAN_1982__261_182872