TY  - JOUR
AU  - V. A. Il'in
TI  - Necessary and sufficient conditions for being a Riesz basis of root vectors of second-order discontinuous operators
JO  - Differencialʹnye uravneniâ
PY  - 1986
SP  - 2059
EP  - 2071
VL  - 22
IS  - 12
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1986_22_12_a5/
LA  - ru
ID  - DE_1986_22_12_a5
ER  -