TY  - JOUR
AU  - V. Ya. Ivrii
AU  - V. M. Petkov
TI  - Necessary conditions for the Cauchy problem for non-strictly hyperbolic equations to be well-posed
JO  - Trudy Matematicheskogo Instituta imeni V.A. Steklova
PY  - 1974
SP  - 1
EP  - 70
VL  - 29
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/RM_1974_29_5_a0/
LA  - en
ID  - RM_1974_29_5_a0
ER  -