TY  - JOUR
AU  - Chi-Kwong Li
AU  - Nung-Sing Sze
TI  - Product of operators and  numerical range preserving maps
JO  - Studia Mathematica
PY  - 2006
SP  - 169
EP  - 182
VL  - 174
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.4064/sm174-2-4/
DO  - 10.4064/sm174-2-4
LA  - en
ID  - 10_4064_sm174_2_4
ER  -