Azam Khan Igor Mordatch George W. Fitzmaurice Justin Matejka Gordon Kurtenbach ViewCube: a 3D orientation indicator and controller. 17-25 2008 SI3D http://doi.acm.org/10.1145/1342250.1342253 conf/si3d/2008 db/conf/si3d/si3d2008.html#KhanMFMK08