1. American Coal Ash Association Survey. In: 1996 coal combustion product (CCP) production and use. Alexandria, VA: American Coal Ash Association, 1997.
2. Korcak RF. In: Karlen DL, Wright RJ, Kemper WD, editors. Agricultural utilization of urban and industrial products, special publication No. 58. Madison, WI: American Society of Agronomy, 1995:107–130.
3. Miller WP. In: Karlen DL, Wright RJ, Kemper WD, editors. Agricultural utilization of urban and industrial products, special publication No. 58. Madison, WI: American Society of Agronomy, 1995:183–208.
4. Mengel K, Kirkby EA. Principles of plant nutrition, 3rd ed. Bern, Switzerland: International Potash Institute, 1982:533–543.
5. Utilization and Disposal of Fly Ash and Other Coal Residues in Terrestrial Ecosystems: A Review