[1] P. Lupoli. and D. Mattis; “Float switch construction for monitoring liquid level”; Environment International 14 (1998) IX.
[2] D. Ordolff; “Investigations on the design of floats to control milk meters”; Journal of Agricultural Engineering Research 43 (1989) 113–123.
[3] V. E. Sakharo, S. A. Kuznetsov, B. D. Zaitsev, I. E. Kuznetsova, and S. G. Joshi; “Liquid level sensor using ultrasonic Lamb waves”; Ultrasonics 41 (2003) 319–322.
[4] E. Vargas, R. Ceres, J. M. Marti´n, and L.Caldero´n; “Ultrasonic sensor for liquid-level inspection in bottles”; Sensors and Actuators A: Physical 61 (1997) 256–259.
[5] T. Kabor and R. Werthschützky; “Wafer Level Processing of Overload- Resistant Pressure Sensors”; Procedia Engineering 47 (2012) 615–618.
[6] H. Golnabi; “Design and operation of a fiber optic sensor for liquid level detection”; Optics and Lasers in Engineering 41 (2004) 801–812.
[7] C. Yang, S. Chen, and G. Yang; “Fiber optical liquid level sensor under cryogenic environment”; Sensors and Actuators A: Physical 94 (2001) 69– 75.
[8] A. Jaworek and A. Krupa; “Phase-shift detection for capacitance sensor measuring void fraction in two-phase flow”; Sensors and Actuators A: Physical 160 (2010) 78–86.
[9] F. Lucklum and B. Jakoby; “Novel magnetic–acoustic resonator sensors for remote liquid phase measurement and mass detection”; Sensors and Actuators A: Physical 145-146 (2008) 44–51.
[10] T. Uemura; “Observations of Backscattered Gamma-Rays in a Surface Density Gauge”; Japanese Journal of Applied Physics 4 (1965) 667.
[11] I. A. Henderson and J. McGhee; “Modelling gamma-source backscatter density gauge”; IEE Proceedings 133 (1986) 611-617.
)
