Ikushi Yoda Junichi Tanaka Bisser Raytchev Katsuhiko Sakaue Takenobu Inoue Stereo Camera Based Non-Contact Non-Constraining Head Gesture Interface for Electric Wheelchairs. 740-745 2006 conf/icpr/2006 ICPR (4) http://doi.ieeecomputersociety.org/10.1109/ICPR.2006.1078 db/conf/icpr/icpr2006-4.html#YodaTRSI06