TY  - JOUR
AU  - R.A. NORMAN
TI  - Dehn's Lemma for Certain 4-Manifolds.
JO  - Inventiones mathematicae
PY  - 1969
SP  - 143
EP  - 147
VL  - 7
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM_1969__7_141958/
ID  - IM_1969__7_141958
ER  -