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"Periodic Reinvestigations". Defense Security Service (U.S. Department of Defense). Archived from the original on 9 December 2018. Retrieved 9 December 2018.
"US Spying on Indian Nuclear Scientists". The NSA has been spying on Indian nuclear scientists by tapping phone conversations. 27 September 2007. Archived from the original on 24 February 2019. Retrieved 26 December 2006.