@Misc{ 
  CasRieSci18,
  author = { Castorina, Daniele and Riey, Giuseppe and Sciunzi, Berardino },
  title = { Hopf Lemma and regularity results for quasilinear anisotropic elliptic  equations },
  journal = { Calculus of Variations and Partial Differential Equations },
  year = { 2018 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/4085/ },
  note = { cvgmt preprint}
}