@Article{ 
  SirTerTor18,
  author = { Sire, Yannick and Terracini, Susanna and Tortone, Giorgio },
  title = { On the nodal set of solutions to degenerate or singular elliptic  equations with an application to $s-$harmonic functions },
  journal = { Journal de Mathématiques Pures et Appliquées },
  year = { 2020 },
  doi = { 10.1016/j.matpur.2020.01.010 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/6277/ },
  note = { cvgmt preprint}
}