@Misc{ 
  BreMasOud13,
  author = { Bretin, Elie and Masnou, Simon and Oudet, Edouard },
  title = { Phase-field approximations of the Willmore functional and flow },
  journal = {  },
  year = { 2013 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/2155/ },
  note = { cvgmt preprint}
}