@Misc{ 
  BraSqu17,
  author = { Brasco, Lorenzo and Squassina, Marco },
  title = { Optimal solvability for a nonlocal problem at critical growth },
  journal = { J. Differential Equations },
  year = { 2017 },
  pages = { 21 },
  URL = { http://cvgmt.sns.it/paper/3416/ },
  note = { cvgmt preprint}
}