FOYDALANILGAN ADABIYOTLAR:
1.
David Kahn,
The Codebreakers
1967. pp. 192-195.
2.
Mavis Batey,
Dilly, The Man Who Broke Enigmas
2009. Hard cover, ISBN 978-1-906447-01-4.
3.
Frode Weierud,
Personal correspondence
August 2017.
4.
Dennis Richie,
Dabbling in the Cryptographic World - A Story
Updated 5 May 2000. Retrieved November 2011.
5.
Collection of M-209 patent and license
agreements
A66684. Declassified by NSA on 11 June 2014 (EO 13526).
6.
Jean-Francois Bouchaudy,
M-209 Cryptanalysis
Retrieved July 2016.
Internet saytlar:
https://www.cryptomuseum.com/crypto/usa/jefferson/index.htm
https://www.cryptomuseum.com/crypto/enigma/hist.htm
https://www.cryptomuseum.com/crypto/hagelin/m209/index.htm
