TY  - JOUR
AU  - G. A. Los'
TI  - Theorems on the estimation of the invariant $A_1$ of the characteristic equation for an $n$th order linear homogeneous 

JO  - Differencialʹnye uravneniâ
PY  - 1970
SP  - 561
EP  - 564
VL  - 6
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1970_6_3_a20/
LA  - ru
ID  - DE_1970_6_3_a20
ER  -