@Article{ 
  BraDe Ruf11,
  author = { Brasco, Lorenzo and De Philippis, Guido and Ruffini, Berardo },
  title = { Spectral optimization for the Stekloff--Laplacian: the stability issue },
  journal = { J. Funct. Anal. },
  year = { 2011 },
  pages = { 28 },
  URL = { http://cvgmt.sns.it/paper/1694/ },
  note = { cvgmt preprint}
}