Keywords: Hut3BPStats.jpg Ultra Hut3 Graph png en Number of signals despatched daily form Bletchley Park Hut 3 during WWII From Appendix V of Bennett Ralph 1999 1994 Behind the Battle Intelligence in the War with Germany Pimlico New and Enlarged ed London Random House ISBN 0-7126-6521-8 own TedColes 2011-03-10 Ultra Hut3 Graph png Cc-zero World War II technology History of cryptography Bletchley Park |