TY  - JOUR
AU  - A. I. Perov
TI  - New complete solvability conditions and questions of reducibility
JO  - Doklady Akademii Nauk
PY  - 1969
SP  - 26
EP  - 29
VL  - 186
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1969_186_1_a5/
LA  - ru
ID  - DAN_1969_186_1_a5
ER  -