@manual{        fk:fsp,
  author        = "Florent Kirchner and Claudio {Sacerdoti Coen}",
  title         = "The \textsf{Fellowship} proof manager",
  howpublished  = "\url{www.lix.polytechnique.fr/Labo/Florent.Kirchner/fellowship/}",
  year          = 2007
}