TY  - JOUR
AU  - K. V. Mal'kov
AU  - M. M. Khapaev
TI  - Some methods in perturbation theory connected with averaging
JO  - Differencialʹnye uravneniâ
PY  - 1987
SP  - 1693
EP  - 1704
VL  - 23
IS  - 10
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1987_23_10_a4/
LA  - ru
ID  - DE_1987_23_10_a4
ER  -