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\begin{thebibliography}{Refrence}
\bibitem {jahan1}
Akyildiz and W. Su and Y. Sankarasubramaniam and E. Cayirci, “A Survey on Sensor Networks”, \textit{IEEE Communications Magazine}, vol 40, Issue 8, pp. 102-114, 2002.
\bibitem {jahan2}
[Akyildiz I. F., W. Su, Y. Sankarasubramaniam, E. Cayirci.,“ Wireless sensor networks: a survey” , Journal of Computer Networks, Vol. 38, March 2002, pp. 393-422.

\bibitem {jahan2} Min R., M. Bhardwaj, S. Cho, E. Shih, A. Sinha, A. Wang,and A. Chandrakasan, Low Power Wireless Sensor Networks” , Proc. of Internation Conf. on VLSI Design,Bangalore, India, Jan. 2001, pp. 205-210.

\end{thebibliography}
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