TY  - JOUR
AU  - L. E. Isaev
TI  - A certain class of operators with spectrum concentrated at zero
JO  - Doklady Akademii Nauk
PY  - 1968
SP  - 783
EP  - 785
VL  - 178
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1968_178_4_a7/
LA  - ru
ID  - DAN_1968_178_4_a7
ER  -