T. S. Steenhuis, Van Es, H. M., Parlange, J. Y., Baveye, P., Walter, M. F., Geohring, L. D., Hutson, J. L., Richard, T. L., Bell, J. L., Boll, J., and , “Hydrology and the Environment.”,
New York's Food and Life Sciences Quarterly, vol. 20, pp. 15–19, 1990.