Spy Satellite History

Grab and Poppy, America's Early ELINT Satellites (PDF):
http://www.nro.gov/history/csnr/programs/docs/prog-hist-03.pdf

Declassified NRO/U.S. Navy Program C ELINT Satellites (PDF)
http://www.nro.gov/foia/docs/U.S.%20Navy-NRO%20Program%20C%20Electronic%20Intelligence%20Satellites%20%281958-1977%29.pdf

History of the Poppy Satellite System, NRO, Program C (PDF)
http://www.governmentattic.org/6docs/NRO-HistoryPOPPY_1978.pdf





Corona - America's First Satellite program (PDF)
https://www.cia.gov/library/center-for-the-study-of-intelligence/csi-publications/books-and-monographs/corona.pdf

Corona history at NRO
http://www.nro.gov/history/csnr/corona/





Declassified US Spy Satellites Reveal Rare Look at Secret Cold War Space Program
http://www.space.com/12996-secret-spy-satellites-declassified-nro.html

Declassified GAMBIT and HEXAGON Videos
http://www.nro.gov/foia/declass/GAMBHEX%20Videos.html