@Misc{ 
  cargalsan08,
  author = { Carlier, Guillaume and Galichon, Alfred and Santambrogio, Filippo },
  title = { From Knothe's transport to Brenier's map and a continuation method for optimal transport  },
  journal = { SIAM J. Math. An. },
  year = { 2009 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/1523/ },
  note = { cvgmt preprint}
}