TY  - JOUR
AU  - Qihong Fan
AU  - M.W. Wong
TI  - A characterization of some non-elliptic pseudo-differential operators as Fredholm operators.
JO  - Forum mathematicum
PY  - 1997
SP  - 17
EP  - 28
VL  - 9
IS  - 2
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/FORUM_1997__9_2_141791/
ID  - FORUM_1997__9_2_141791
ER  -