Assertion: outer space | /r/HasProperty | introduced
Facets:
Source sentences:
text: Outer space X n is contractible and the action of Out( F n ) on X n is properly discontinuous, as was proved by Culler and Vogtmann in their original 1986 paper  where Outer space was introduced.
text: is contractible and the action of Out( ) on is properly discontinuous, as was proved by Culler and Vogtmann in their original 1986 paper where Outer space was introduced.