TY  - JOUR
AU  - S. S. Kharibegashvili
TI  - A characterization problem for a class of second-order hyperbolic systems with a characteristic line of degeneration
JO  - Differencialʹnye uravneniâ
PY  - 1990
SP  - 305
EP  - 313
VL  - 26
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1990_26_2_a15/
LA  - ru
ID  - DE_1990_26_2_a15
ER  -