pages={92--97},
year={2015},
organization={IEEE}
-}
\ No newline at end of file
+}
+
+@article{ref226,
+ title={Extending the Network Lifetime of Wireless Sensor Networks Using Residual Energy Extraction—Hybrid Scheduling Algorithm},
+ author={CHITRA, M},
+ journal={Int'l J. of Communications, Network and System Sciences},
+ volume={2010},
+ year={2010},
+ publisher={Scientific Research Publishing}
+}
+
+@article{ref227,
+ author = {Mihaela Cardei and
+ David MacCallum and
+ Maggie Xiaoyan Cheng and
+ Manki Min and
+ Xiaohua Jia and
+ Deying Li and
+ Ding-Zhu Du},
+ title = {Wireless Sensor Networks with Energy Efficient Organization},
+ journal = {Journal of Interconnection Networks},
+ volume = {3},
+ number = {3-4},
+ year = {2002},
+ pages = {213-229},
+}
+
+@inproceedings{ref228,
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+ title = {B\{GOP\}: an adaptive coverage algorithm for wireless sensor networks},
+ booktitle = {Proceedings of the 13th European Wireless Conference},
+ series = {EW'07},
+ year = {2007},
+ location = {Paris, France},
+
+}
+