TY  - JOUR
AU  - Dieter Lutz
TI  - On bounded time-dependent perturbations of operator cosine functions.
JO  - Aequationes mathematicae
PY  - 1981
SP  - 197
EP  - 203
VL  - 23
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/AM2_1981__23_136910/
ID  - AM2_1981__23_136910
ER  -