Robert Söderberg Klas Nordberg Gösta H. Granlund An Invariant and Compact Representation for Unrestricted Pose Estimation. 3-10 2005 conf/ibpria/2005-1 IbPRIA (1) http://dx.doi.org/10.1007/11492429_1 db/conf/ibpria/ibpria2005-1.html#SoderbergNG05