@Misc{ 
  fergazwet05,
  author = { Ferrero, Alberto and Gazzola, Filippo and Weth, Tobias },
  title = { Positivity, symmetry and uniqueness for minimizers of second order Sobolev inequalities },
  journal = { Ann. Mat. Pura Appl. },
  year = { 2005 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/1396/ },
  note = { cvgmt preprint}
}