@InCollection{AehligNipkow08,
  author =       {Aehlig, Klaus and Nipkow, Tobias},
  title =        {Normalization by Evaluation},
  booktitle =    {The Archive of Formal Proofs},
  publisher =    {\url{http://afp.sourceforge.net/entries/NormByEval.shtml}},
  year =         2008,
  editor =       {Gerwin Klein and Tobias Nipkow and Lawrence Paulson},
  month =        jan
}