Ansoult, M., Debacker, LW., & Declercq, M. (1985). Statistical Relationship Between Apparent Dielectric-constant and Water-content in Porous-media. Soil Science Society of America Journal, 49(1), 47-50. https://doi.org/10.2136/sssaj1985.03615995004900010009x (Original work published 1985)