8Topp G C. Measurement of soil water content using TDR: a field evaluation[J]. Soil Sci Am J, 1985, 49:19 -24.
9Topp G C, Davis J L, Annan A P. Electromagnetic determination of soil water content: measurement in coaxial transmission lines[J]. Water Resources Research, 1980, 16:574 - 582.
10Skierucha W, Wilczek A, Alokhina O. Calibration of a TDR probe for low soil water content measurements[J]. Sensors and Actuators A: Physical, 2008,147:544-552.