TY  - JOUR
AU  - Kolev, Dimitar
TI  - Involutivity and Symple Waves in R^2
JO  - Serdica Mathematical Journal
PY  - 1997
SP  - 225
EP  - 232
VL  - 23
IS  - 3-4
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/SMJ2_1997_23_3-4_a3/
LA  - en
ID  - SMJ2_1997_23_3-4_a3
ER  -