\begin{thebibliography}{1}

\bibitem{BollobasRiordan}
B{\'e}la Bollob\'{a}s and Oliver Riordan.
\newblock A short proof of the harris-keston theorem.
\newblock {\em Bull. London Math. Soc.}, 38:470--484, August 2006.

\end{thebibliography}
