TY  - JOUR
AU  - A. Halanay
AU  - Sh. Shandor
TI  - Sturm type theorems for self-conjugate systems of higher order differential equations
JO  - Doklady Akademii Nauk
PY  - 1957
SP  - 506
EP  - 507
VL  - 114
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DAN_1957_114_3_a14/
LA  - ru
ID  - DAN_1957_114_3_a14
ER  -