Astera, Michael. With Agricola. The Ideal Soil 2014: A Handbook for the New Agriculture v2.0. Michael Astera, 2014. Print.

PhD. Albrecht, William A. Albrecht’s Foundation Concepts. Vol. 1. Ed. Charles Walters. Austin: Acres USA, 1975/2011. Print.

PhD. Albrecht, William A. Soil Fertility & Animal Health. Vol. 2. Ed. Charles Walters. Austin: Acres USA, 1975/2005. Print.

PhD. Albrecht, William A. Albrecht’s Hidden Lessons. Vol. 3. Ed. Charles Walters. Austin: Acres USA, 1989/2013. Print.

PhD. Albrecht, William A. Albrecht’s Enduring Vision. Vol. 4. Ed. Charles Walters. Austin: Acres USA, 1992/2013. Print.

PhD. Albrecht, William A. Albrecht on Calcium. Vol. 5. Ed. Charles Walters. Austin: Acres USA, 2011. Print.

PhD. Albrecht, William A. Albrecht on Pastures. Vol. 6. Ed. Charles Walters. Austin: Acres USA, 2011. Print.

PhD. Albrecht, William A. Albrecht on Soil Balancing. Vol. 7. Ed. Charles Walters. Austin: Acres USA, 2011. Print.

PhD. Albrecht, William A. Soil Fertility & Human and Animal Health. Vol. 8. Ed. Charles Walters. Austin: Acres USA, 2013. Print.

PhD. Jones, Christine. Interview with Tracy Frisch. “SOS: Save Our Soils.” Dr. Jones: Dr. Christine Explains The Life-Giving Link Between Carbon and Healthy Topsoil. Acres USA, 15 March 2015. Vol. 45. No. 3.

Zimmer, Gary F. The Biological Farmer. Acres USA, 2000. Print.

Fallon, Sally, with Mary Enig. Nourishing Traditions. New Trends, 2001. Print.

Walters, Charles. Weeds, Control Without Poisons. 2nd ed. Acres USA, 1991/1999. Print.

Swerczek, T.W. “Nitrate Toxicity and Sodium Deficiency Associated with Hypomagnesemia, Hypocalcemia and the Grass Tetany Syndrome in Herbivores.”

Annual Growers Nutritional Minerals Meeting. Milan, Ohio. 4 December 2007. Conference Presentation.

Walters, Charles, and C. J. Fenzau. Eco-Farm. Acres USA, 1996. Print.

Bohn, Hinrich L., Rick A. Myer, and George A. O’Connor. Soil Chemistry. 2nd ed. Wiley-Interscience. 1985. Print.

Andersen, Arden. Science in Agriculture. Acres USA, 2000. Print.

DVM. Skow, Dan, and Charles Walters. Mainline Farming for Century 21. Acres USA, 1995. Print.

Haas, Elson. Staying Healthy with Nutrition. Celestial Arts, 1992. Print.

Price, Weston A. Nutrition and Physical Degeneration. Price-Pottenger Nutrition Foundation, 1939/2004. Print.

Foth and Ellis. Soil Fertility. John Wiley and Sons, 1988. Print.

Sait, Graeme. Nutrition Rules. Soil Therapy Pty Ltd, 2003. Print.

Hess (rev. by Thomas) Chemistry Made Simple. Doubleday, 1984. Print.

Walters, Charles, with Dr. Richard Olree. Minerals for the Genetic Code. Acres USA, 2006. Print.

McCaman, Jay L. When Weeds Talk. 2nd ed. of Weeds and Why They Grow.

Retitled, When Weeds Talk. MO, 2013. Print.

Walters, Charles. Grass, the Forgiveness of Nature. Acres USA, 2006. Print.

Pfieffer, Ehrenfried E. Weeds & What They Tell Us. 3rd ed. Floris Books, 2012. Print.

PhD. Andersen, Arden B. Science In Agriculture. Austin: Acres USA, 1992/2000. Print.

Schriefer, Donald L. From the Soil Up. 2nd ed. Austin: Acres USA, 1984/2000. Print.

Callahan, Philip S. Paramagnetism: Rediscovering Nature’s Secret Force of Growth. Austin: Acres USA, 1995. Print.

Beck, Malcolm. Lessons in Nature. Austin: Acres USA, 1991/2005. Print.

Nardi, James B. Life in the Soil: A Guide for Naturalists and Gardeners. University of Chicago Press, 2007. Print.

The Purdue OWL Family of Sites. The Writing Lab and OWL at Purdue and Purdue U, 2008. Web. 27 Jan. 2016.