TY  - JOUR
AU  - I. A. Pavlyuk
TI  - The investigation of nonautonomous systems of second order differential equations by means of differential invariants
JO  - Differencialʹnye uravneniâ
PY  - 1968
SP  - 1785
EP  - 1800
VL  - 4
IS  - 10
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1968_4_10_a3/
LA  - ru
ID  - DE_1968_4_10_a3
ER  -