TY  - JOUR
AU  - McCool, James
TI  - The Coherence Number of 2-Groups
JO  - Canadian mathematical bulletin
PY  - 1990
SP  - 503
EP  - 508
VL  - 33
IS  - 4
UR  - http://geodesic.mathdoc.fr/articles/10.4153/CMB-1990-080-1/
DO  - 10.4153/CMB-1990-080-1
ID  - 10_4153_CMB_1990_080_1
ER  -