@Article{ 
  FraPraSte21,
  author = { Franceschi, Valentina and Pratelli, Aldo and Stefani, Giorgio },
  title = { On the Steiner property for planar minimizing clusters. The isotropic case. },
  journal = { Commun. Contemp. Math. },
  year = { 2023 },
  doi = { https://doi.org/10.1142/S0219199722500407 },
  volume = { 25 },
  number = { 5 },
  pages = { 2250040, 29 pp. },
  URL = { http://cvgmt.sns.it/paper/5164/ },
  note = { cvgmt preprint}
}