@Misc{ 
  AmCoDeFi11,
  author = { Ambrosio, Luigi and Colombo, Maria and De Philippis, Guido and Figalli, Alessio },
  title = { Existence of Eulerian solutions to the semigeostrophic equations in
  physical space: the 2-dimensional periodic case },
  journal = { Comm. Partial Differential Equations },
  year = { 2012 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/1700/ },
  note = { cvgmt preprint}
}