@Misc{ 
  PetZüs14,
  author = { Petrache, Mircea and Züst, Roger },
  title = { Matchings in metric spaces, the dual problem and calibrations modulo 2 },
  journal = {  },
  year = { 2014 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/2528/ },
  note = { cvgmt preprint}
}