Adams, J.A. 1986. . College Station, Texas : Texas A&M University Press ISBN 0-89096-301-0 Soil Survey Staff. (1975) USDA-SCS Agric. Handb. 436. U.S. Gov. Print. Office. Washington DC. Soil Survey Division Staff. (1993) . Soil Conservation Service. U.S. Department of Agriculture Handbook 18. Logan, W. B., Dirt: The ecstatic skin of the Earth, 1995. ISBN 1-57322-004-3. Faulkner, William. Plowman's Folly. New York, Grosset & Dunlap forlag, 1943. ISBN 0-933280-51-3. Jenny, Hans, Factors of Soil Formation: A System of Quantitative Pedology, 1941. Edward Hyams: Jordsmonn & sivilisasjon, Nisus forlag, 2014.