" Singh, S. The code book: The secret history of codes and code-breaking. Forth Estate Ltd.
Lua i Stíl Chicago (17ú heag.)" Singh, Simon". The Code Book: The Secret History of Codes and Code-breaking. Forth Estate Ltd.
Lua MLA (9ú heag.)" Singh, Simon". The Code Book: The Secret History of Codes and Code-breaking. Forth Estate Ltd.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.