Olivier Buisson Bernard Besserer Samia Boukir F. Helt 78-84 1997 conf/cvpr/1997 CVPR https://doi.org/10.1109/CVPR.1997.609301 https://doi.ieeecomputersociety.org/10.1109/CVPR.1997.609301 db/conf/cvpr/cvpr1997.html#BuissonBBH97