@Article{	  naccache99how,
  author =	 {David Naccache and Adi Shamir and Julien P. Stern},
  title =	 {How to copyright a function?},
  journal =	 {Public Key Encryption '99, Lecture Notes in Computer
                  Science},
  year =	 1999,
  editor =	 {Hideki Imai},
  publisher = {Springer-Verlag},
  series =	 {Lecture Notes in Computer Science},
  url =
                  {http://www.julienstern.org/files/funcopy/funcopy.html},
  section = {SOFTWARE-WATERMARKING}
}