TY  - JOUR
AU  - Philip R. Heath
TI  - Groupoid Operations and Fibre-Homotopy Equivalence. I.
JO  - Mathematische Zeitschrift
PY  - 1973
SP  - 207
EP  - 234
VL  - 130
UR  - http://geodesic.mathdoc.fr/item/MZ_1973__130_171863/
ID  - MZ_1973__130_171863
ER  -