Jelaskan Rujukan dari Telegram Zimmermann dalam bahasa melayu

Room 40: British Naval Intelligence, 1914-1918, by Patrick Beesly. New York: Harcourt, Brace, Jovanovich, 1982 ISBN 0-15-178634-8

On Secret Service East of Constantinople, by Peter Hopkirk. Oxford University Press, 1994 ISBN 0-19-280230-5

The Zimmermann Telegram, by Barbara W. Tuchman, Ballantine Books, 1958 ISBN 0-345-32425-0

The Zimmermann Telegram of January 16 1917 and its Cryptographic Background by William F. Friedman and Charles J. Mendelsohn: . War Department, Office of the Chief Signal Officer, Washington, GPO, 1938

'Telegram that brought US into Great War is Found'  London Daily Telegraph, 17 October 2005. Article by Ben Fenton