TY  - JOUR
AU  - G.E. BREDON
AU  - J.W. WOOD
TI  - Non-Orientable Surfaces in Orientable 3-Manifolds.
JO  - Inventiones mathematicae
PY  - 1969
SP  - 83
EP  - 110
VL  - 7
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM_1969__7_141954/
ID  - IM_1969__7_141954
ER  -