@Misc{ 
  CheFig17,
  author = { Chen, Shibing and Figalli, Alessio },
  title = { Partial $W^{2,p}$ regularity for optimal transport maps },
  journal = { J. Funct. Anal. },
  year = { 2017 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/3354/ },
  note = { cvgmt preprint}
}