TY  - JOUR
AU  - Humphries, Stephen P.
TI  - Normal closures of powers of Dehn twists in mapping class groups
JO  - Glasgow mathematical journal
PY  - 1992
SP  - 314
EP  - 317
VL  - 34
IS  - 3
UR  - http://geodesic.mathdoc.fr/articles/10.1017/S0017089500008879/
DO  - 10.1017/S0017089500008879
ID  - 10_1017_S0017089500008879
ER  -