@Article{ 
  Per23,
  author = { Perugini, Matteo },
  title = { Perimeter inequality under circular and Steiner symmetrisation: geometric characterisation of extremals },
  journal = { Nonlinear Analysis },
  year = { 2023 },
  pages = { 22 },
  URL = { http://cvgmt.sns.it/paper/6306/ },
  note = { cvgmt preprint}
}