\begin{thebibliography}{1}

\bibitem{BihamSh93}
E.~Biham and A.~Shamir.
\newblock {\em A Differential Cryptanalysis of the {D}ata {E}ncryption 
{S}tandard}.
\newblock Springer-Verlag, 1993.

\bibitem{Matsui94}
Mitsuru Matsui.
\newblock The first experimental cryptanalysis of the {D}ata {E}ncryption 
{S}tandard.
\newblock In Yvo~G. Desmedt, editor, {\em Proceedings CRYPTO 94}, pages 1--11.
  Springer, 1994.
\newblock Lecture Notes in Computer Science No.\ 839.

\end{thebibliography}
