Campbell, Duncan (April 1999). "Interception Capabilities 2000". www.fas.org. Federation of American Scientists. Archived from the original on 25 March 2013. Retrieved 21 April 2013.
web.archive.org
Campbell, Duncan (April 1999). "Interception Capabilities 2000". www.fas.org. Federation of American Scientists. Archived from the original on 25 March 2013. Retrieved 21 April 2013.