TY  - JOUR
AU  - V. Ya. Ivrii
TI  - The energy integral for nonstrictly hyperbolic operators
JO  - Trudy Matematicheskogo Instituta imeni V.A. Steklova
PY  - 1975
VL  - 30
IS  - 6
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/RM_1975_30_6_a12/
LA  - ru
ID  - RM_1975_30_6_a12
ER  -