@Misc{ 
  DePFig12,
  author = { De Philippis, Guido and Figalli, Alessio },
  title = { Second order stability for the Monge-Ampere equation and strong Sobolev
  convergence of optimal transport maps },
  journal = { Anal. PDE },
  year = { 2012 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/1778/ },
  note = { cvgmt preprint}
}