1. A. Nilsson. IAEA illicit trafficking database. http://www-ns.iaea.org/downloads/security/itdb-fact-sheet-2009.pdf, 2009 (accessed 05.12.11).
2. The Biological Threat to U.S. Water Supplies: Toward a National Water Security Policy
3. F. Gottron, D. Shea, Ricin: technical background and potential role in terrorism, Congressional Research Service, The Library of Congress, Washington, DC, RS 21383, 2004.
4. The Washington Times;Carter,2009
5. C. Arthur, Radioactive materials stolen by terrorists. The Independent 2001, 2011. www.independent.co.uk/../radioactive-materials-stolen-by-terrorists-684247.html (accessed 05.12.11).