@ARTICLE{2009-LAA-HHM,
  author = {E. Haber and S. Heldmann and J. Modersitzki},
  title = {A Framework for Image-Based Constrained Registration with an Application to Local Rigidity},
  journal = {Linear Algebra and its Applications},
  volume = {431},
  year = {2009},
  pages = {459--470},
}