@inproceedings{makadia03cvpr,
  author    = {Ameesh Makadia and Kostas Daniilidis},
  title     = {Direct {3D}-Rotation Estimation from Spherical Images via a Generalized Shift Theorem},
  booktitle = {{IEEE} Conference on Computer Vision and Pattern Recognition (CVPR)},
  pages     = {217--226},
  year      = {2003},
}