%0 Journal Article
%A Stefan Czerwik
%T Multi-valued contraction mappings in metric spaces.
%J Aequationes mathematicae
%D 1977
%P 297-302
%V 16
%I mathdoc
%U http://geodesic.mathdoc.fr/item/AM2_1977__16_136701/
%F AM2_1977__16_136701