%0 Journal Article
%A McAdam, Stephen
%T Going Down and Open Extensions
%J Canadian journal of mathematics
%D 1975
%P 111-114
%V 27
%N 1
%U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1975-013-5/
%R 10.4153/CJM-1975-013-5
%F 10_4153_CJM_1975_013_5