@Article{ 
  Vel13,
  author = { Velichkov, Bozhidar },
  title = { A note on the monotonicity formula of Caffarelli-Jerison-Kenig },
  journal = { Rend. Lincei Mat. Appl. },
  year = { 2014 },
  volume = { 25 },
  pages = { 165--189 },
  URL = { http://cvgmt.sns.it/paper/2266/ },
  note = { cvgmt preprint}
}