TY  - JOUR
AU  - U. D. Bekbaev
TI  - On the equivalence and differential rational invariants of second-order linear partial differential equations of two variables under a change of variables
JO  - Differencialʹnye uravneniâ
PY  - 1998
SP  - 835
EP  - 837
VL  - 34
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/DE_1998_34_6_a16/
LA  - ru
ID  - DE_1998_34_6_a16
ER  -