J. Estrin, and S. Kumar. Proceedings of the fifth annual ACM/IEEE international conference on Mobile computing and networking, page 263-270. Seattle, WA USA, (1999)
J. Polastre, J. Hill, and D. Culler. Proceedings of the 2nd ACM Conference on Embedded Networked Sensor Systems (SenSys), page 95--107. Baltimore, MD, USA, (November 2004)