1. U.S. EPA (2015) Fertilizer and fertilizer production waste, U.S. EPA, Washington D.C., USA. http://www.epa.gov/radiation/tenorm/fertilizer.html . Accessed 05 Jan 2015
2. Toxicological profile of radium, Agency for Toxic Substance and Registry (ATSDR), Atlanta, GA, USA. http://www.atsdr.cdc.gov/ToxProfiles/tp.asp?id=791&tid=154 . Accessed 06 Jan 2015
3. Eisenbud M, Gesell T (1997) Environmental radioactivity. Academic Press, San Diego
4. Shleien B (1992) Handbook of health physics and radiological health. Scinta Inc., Silver Spring
5. Righi S, Lucialli P, Bruzzi L (2005) Health and environmental impacts of a fertilizer plant Part I: assessment of radioactive pollution. J Environ Radioact 82(2):167–182