TY  - JOUR
AU  - Carvalho e Silva, Jaime
TI  - On the hyperbolicity of a third order operator and the generalized Goursat-Darboux problem
JO  - Portugaliae mathematica
PY  - 1989
SP  - 567
EP  - 577
VL  - 46
IS  - S
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/PORMA_1989__46_S_115833/
LA  - en
ID  - PORMA_1989__46_S_115833
ER  -