@Misc{ 
  Cri13,
  author = { Crippa, Gianluca },
  title = { Ordinary Differential Equations and Singular Integrals },
  journal = {  },
  year = { 2013 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/2121/ },
  note = { cvgmt preprint}
}