@Article{ 
  PraRizSer15,
  author = { Prandi, Dario and Rizzi, Luca and Seri, Marcello },
  title = { A sub-Riemannian Santaló formula with applications to isoperimetric  inequalities and first Dirichlet eigenvalue of hypoelliptic operators },
  journal = { Journal of Differential Geometry },
  year = { 2015 },
  doi = { 10.4310/jdg/1549422105 },
  volume = { 111 },
  number = { 2 },
  pages = { 339-379 },
  URL = { http://cvgmt.sns.it/paper/2804/ },
  note = { cvgmt preprint}
}