@Misc{ 
  BucFra21,
  author = { Bucur, Dorin and Fragalà, Ilaria },
  title = { Rigidity for measurable sets },
  journal = {  },
  year = { 2021 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/5049/ },
  note = { cvgmt preprint}
}