The Samos E or SAMOS (Satellite and Missile Observation System) program was a relatively short-lived series of reconnaissance satellites for the United States
The NRO has been intertwined with innovation since its inception.
Reconnaissance satellites which form the principal component of the Satellite Early Warning System currently used by the United States.
Miscellaneous Records on Spy Satellites
One of the Navy’s most advanced deep sea submersible at the time, surfaced with part of a U.S. spy satellite, codenamed HEXAGON.
History of Satellite Reconnaissance
The RECON - National Reconnaissance Office (NRO) Publication
The NRO - Its Mission, History, and People
National Reconnaissance Office (NRO) Directives
Corona Satellite / Discoverer Program