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+ journal={Computer Communications},
+ volume={31},
+ number={4},
+ pages={770--781},
+ year={2008},
+ publisher={Elsevier}
+}
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+@article{ref237,
title={Hilbert mobile beacon for localisation and coverage in sensor networks},
author={Bahi, Jacques M and Makhoul, Abdallah and Mostefaoui, Ahmed},
journal={International Journal of Systems Science},
year={2008},
publisher={Taylor \& Francis}
}
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+ year={2009},
+ publisher={Wiley}
+}