@Misc{ 
  brasan,
  author = { Brasco, Lorenzo and Santambrogio, Filippo },
  title = { An equivalent path functional formulation of branched transportation problems },
  journal = { Discrete Contin. Dyn. Syst. },
  year = { 2010 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/38/ },
  note = { cvgmt preprint}
}