TY  - JOUR
AU  - V. A. Il'in
TI  - Necessary and sufficient conditions for a subsystem of the eigen- and associated functions of a Keldys bundle of ordinary differential operators to be a basis
JO  - Doklady Akademii Nauk
PY  - 1976
SP  - 796
EP  - 799
VL  - 227
IS  - 4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1976_227_4_a5/
LA  - ru
ID  - DAN_1976_227_4_a5
ER  -