TY  - JOUR
AU  - N. A. Lukashevich
AU  - V. I. Matatov
TI  - Second order systems without moving critical singular points
JO  - Differencialʹnye uravneniâ
PY  - 1973
SP  - 449
EP  - 455
VL  - 9
IS  - 3
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1973_9_3_a5/
LA  - ru
ID  - DE_1973_9_3_a5
ER  -