\begin{thebibliography}{CLRS01}

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\newblock MIT Press, 2001.

\bibitem[GJ79]{Garey}
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\newblock W. H. Freeman Company, San Francisco, 1979.

\bibitem[Wil02]{Wilf1}
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\newblock {\em Algorithms and Complexity}.
\newblock A K Peters, Ltd., 2002.

\end{thebibliography}