[1] Yuan, X.P. and Chen, Y. (2009) Commonly Used Research Methods in Liquid Level Detection. Energy Technology and Management, 1, 120-122.
[2] Yang, Z.H. and Li, H. (2009) Situation and Development Trend of New Liquid Level Detection Technology. Industry and Mine Automation, 6, 61-64.
[3] Tomasik, M., Juszka, H. and Lis, S. (2012) Communication System Control and Measurement System in the Autonomous Milking Machine. Inzynieria Rolnicza, 16, 303-310.
[4] CLC Series Miniature Capacitive Continuous Liquid Level Sensors Datasheet. Sensor Technics. www.sensortechnics.com
[5] Greene, C.E., Harrist, D.W. and McElhinny, M.T. (2007) Implementation of a Wireless Power Transmitter and Method. US Patent.
[6] Shearer, J.G., Greene, C.E. and Harrist, D.W. (2010) Power Transmission Network. US Patent.
[7] Datasheet, P. (2011) P2110-915MHz RF Power Harvester Receiver. Powercast Corporation.
[8] User Manual of Lifetime Power Energy Harvesting Development Kit for Wireless Sensors. www.powercastco.com