TY  - JOUR
AU  - Z. I. Ismailov
TI  - Formally normal extensions of an operator
JO  - Differencialʹnye uravneniâ
PY  - 1992
SP  - 905
EP  - 907
VL  - 28
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1992_28_5_a22/
LA  - ru
ID  - DE_1992_28_5_a22
ER  -