TY  - JOUR
AU  - I. Berstein
AU  - Tudor Ganea
TI  - The category of a map and of a cohomology class
JO  - Fundamenta Mathematicae
PY  - 1961
SP  - 265
EP  - 279
VL  - 50
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.4064/fm-50-3-265-279/
DO  - 10.4064/fm-50-3-265-279
LA  - en
ID  - 10_4064_fm_50_3_265_279
ER  -