@Misc{ 
  ChaDeP12,
  author = { Champion, Thierry and De Pascale, Luigi },
  title = { On the twist condition and c-monotone transport plans },
  journal = {  },
  year = { 2012 },
  pages = { 16 },
  URL = { http://cvgmt.sns.it/paper/1974/ },
  note = { cvgmt preprint}
}