TY  - JOUR
AU  - Scherk, P.
TI  - On the Exactness of the Homotopy Sequence
JO  - Canadian mathematical bulletin
PY  - 1964
SP  - 617
EP  - 618
VL  - 7
IS  - 4
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1964-058-9/
DO  - 10.4153/CMB-1964-058-9
ID  - 10_4153_CMB_1964_058_9
ER  -