@Misc{ 
  MonRiv13,
  author = { Mondino, Andrea and Rivière, Tristan },
  title = { A frame energy for immersed tori and applications to regular homotopy classes },
  journal = { Journal of Differential Geometry },
  year = { 2013 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/2214/ },
  note = { cvgmt preprint}
}