see url:
https://www.nsa.gov/about/cryptologic-heritage/museum/exhibits/#kahn_collection
see url: https://twitter.com/NatCryptoMuseum
Quote<<<
Looking for information on cryptologic history? Look no further! NCM’s
David Kahn Collection contains 3,885 books, 130,000 pages of research
notes, and 54 boxes of correspondence from historian/author Kahn’s
personal research library
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