@Misc{ 
  ambber08,
  author = { Ambrosio, Luigi and Bernard, Patrick },
  title = { Uniqueness of signed measures solving the continuity equation for Osgood vector fields },
  journal = {  },
  year = { 2008 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/1321/ },
  note = { cvgmt preprint}
}