@Misc{ 
  CatMasDar14,
  author = { Catino, Giovanni and Dario D. Monticelli,  and Mastrolia, Paolo },
  title = { A variational characterization of flat spaces in dimension three },
  journal = {  },
  year = { 2014 },
  pages = {  },
  URL = { https://gecogedi.dimai.unifi.it/paper/531/ },
  note = { cvgmt preprint}
}