%0 Journal Article
%A Stefan Czerwik
%T Multi-valued contraction mappings in metric spaces. (Short Communication).
%J Aequationes mathematicae
%D 1977
%P 188-189
%V 16
%I mathdoc
%U http://geodesic.mathdoc.fr/item/AM2_1977__16_136690/
%F AM2_1977__16_136690