TY  - JOUR
AU  - Jan Boman
TI  - The sum of two plane convex C... sets is not always C...
JO  - Mathematica Scandinavica
PY  - 1990
SP  - 216
EP  - 224
VL  - 66
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/MS2_1990__66_1_167106/
ID  - MS2_1990__66_1_167106
ER  -