TY  - JOUR
AU  - Engelking, Ryszard
TI  - An elementary proof of Noble's theorem on normality of powers
JO  - Commentationes Mathematicae Universitatis Carolinae
PY  - 1988
SP  - 677
EP  - 678
VL  - 29
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/CMUC_1988__29_4_a5/
LA  - en
ID  - CMUC_1988__29_4_a5
ER  -