@Article{ 
  FrMoRiSi20,
  author = { Franceschi, Valentina and Monti, Roberto and Righini, Alberto and Sigalotti, Mario },
  title = { The isoperimetric problem for regular and crystalline norms in $\mathbb H^1$ },
  journal = { Journal of Geometric Analysis },
  year = { 2020 },
  doi = { 10.1007/s12220-022-01045-4 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/4769/ },
  note = { cvgmt preprint}
}