TY  - JOUR
AU  - Doan The Hieu
AU  - Tran Le Nam
TI  - On the four vertex theorem in planes with
 radial density $e^{\varphi(r)}$
JO  - Colloquium Mathematicum
PY  - 2008
SP  - 169
EP  - 174
VL  - 113
IS  - 1
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/articles/10.4064/cm113-1-10/
DO  - 10.4064/cm113-1-10
LA  - en
ID  - 10_4064_cm113_1_10
ER  -