Cover Note from William Friedman Re Patents; Note from William Friedman to CIA

Document A104949

33.2 KiB

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Cover Note to William Friedman Re Patents; Note from CIA to William Friedman

Document A104946

41.71 KiB

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Cryptographic Apparatus

Document A4161577

2.04 MiB

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Difference Between William Friedman's Patents and Durkee's Patent; Note to William Friedman from NSA R&D

Document A104953

39.55 KiB

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Dualex Corporation, A Patent Holding Company; Memo from Special Assistant to Chief, R&D to William Friedman

Document A104970

57.33 KiB

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Dualex Telegraph Equipment and Patents Issued; Internal NSA Note to William Friedman

Document A104966

36.05 KiB

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Note from William Friedman Requesting Return of Patents; Note from William Friedman to CIA

Document A104957

33.6 KiB

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U.S. Patent No. 2,552,548 for Facsimile Enciphering System; Letter from William Friedman to Vice President, Western Union Telegraph Company

Document A104975

343.21 KiB

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W.F. Friedman Facsimile Enciphering System

Document A4161579

4.74 MiB

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W.F. Friedman Printing Telegraph System

Document A4161578

867.78 KiB

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William Friedman's Patents No. 1,530,660 & 1,694,874 Vs Durkee's Patent; Note from Friedman to NSA R&D

Document A104962

37.96 KiB

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