Nielsen, D.C., Lagae, H.L., Anderson, R.L. 1995. Time-Domain Reflectometry Measurements of Soil Water Content. Soil Science of America Journal, vol. 59: 103-105.
Lagae, H.L. 1999, Soil organic matter - the missing piece of the productivity puzzle? Deriving an estimate of the economic value of soil organic matter.* Colorado State University. 149 pp. (M.S. Thesis)
* Goes to a non-ARS website