@Article{ 
  BoLaMaSc11,
  author = { Bonfiglioli, Andrea and Lanconelli, Ermanno and Magnani, Valentino and Scienza, Matteo },
  title = { H-convex distributions in stratified groups },
  journal = { Proc. Amer. Math. Soc.  },
  year = { 2013 },
  volume = { 141 },
  number = { 10 },
  pages = { 3633-3638 },
  URL = { http://cvgmt.sns.it/paper/1728/ },
  note = { cvgmt preprint}
}