@Misc{ 
  BraGómVaz20,
  author = { Brasco, Lorenzo and Gómez-Castro, David and Vazquez, Juan Luis },
  title = { Characterisation of homogeneous fractional Sobolev spaces },
  journal = { Calc. Var. Partial Differential Equations },
  year = { 2020 },
  pages = { 31 },
  URL = { http://cvgmt.sns.it/paper/4743/ },
  note = { cvgmt preprint}
}