@Misc{ 
  But22,
  author = { Buttazzo, Giuseppe },
  title = { On the continuity of the Continuous Steiner Symmetrization },
  journal = {  },
  year = { 2022 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/5786/ },
  note = { cvgmt preprint}
}