Bibby Boi

Annotated Bibliography


Primary Sources

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Alan Turing in 1934. 1934. Duncommutin, duncommutin.com/tag/alan-turing/. Accessed 6 Feb. 2020.

This full body photograph depicts Alan Turing, the genius behind the bombe machine. The image was taken when Turing was twenty-two years old.

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"Alan Turing Quotes." Good Reads, 2020, www.goodreads.com/author/quotes/87041.Alan_Turing. Accessed 7 Jan. 2020.

This source provided a number of quotes by Alan, Turing. Several of his sayings and quips were rather inspiring - and sometimes homorous - thus, two of these were used in the "Home" section of the website. The first one conveys the power and intelligence that Turing believed future technology would have, and the second is a testament to his daring and imaginative personality. No one before had considered fighting the Enigma maching with another machine, but Turing did, and he was sucessful.

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Batey, Maevis. "Maevis Batey - Film 3, 4, 10 ,12." Legasee.org.uk, Netfrux Technologies, www.legasee.org.uk/veteran/joy-aylard/. Accessed 31 Jan. 2020. Interview. 

Legasse, a video archive of over six-hundred veteran interviews, provided the wonderful interview of Maevis Batey, an English codebreaker at Bletchley Park. From her kind words toward "Dilly" Knox to her praise of Turing's bombe, Maevis' account of her time at Bletchley supplied essential insights into life in the estate. She explains just how busy codebreakers like her were and how helpful Turing's bombe was as a result of Rejewski's "original breaks."

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Bundesarchiv, Bild. General Heinz Guderian Using an Enigma Machine. Bletchley Park British Cryptanalysis during World War II, 2012, www.bletchleypark.at/ebooks/ChristianLendl_BletchleyParkHQ.pdf. Accessed 6 Feb. 2020.

This is an image inside of the book Bletchley Park British Cryptanalysis during World War II by Christian Lendl. It depicts a German general overseeing the usage of an Enigma machine. This is an example of an Enigma machine being used from the opponent's side from the Allies.

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Convery, Bella. Spy Museum Enigma Replica Photo. 11 Nov. 2019.

This is an image of a replica of an enigma machine that a member of the group viewd in a museum called Spyscape, NYC. This enigma machine was seen in person, and it served to be a first hand experience of the poject topic.

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Draco. Bletchley Park. 2012. bletchleypark.at, CCA, 2008, www.bletchleypark.at/ebooks/ChristianLendl_BletchleyParkHQ.pdf. Accessed 6 Feb. 2020.

This modern-day image of Bletchley Park provided a visual of the secret estate where Alan Turing and other codebreakers worked and the place where many German codes were decrypted through his technology.

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Eastcote Greek Bombe Bay. 1939-1945. Artsandculture.google.com, artsandculture.google.com/asset/eastcote-greek-bombe-bay/IwFMzU3CqbYPkA. Accessed 6 Feb. 2020.

This black and white photograph depicts members of the Women's Royal Naval Service (WRNS) operating the bombe machines which typically ran 24/7.

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Elliot and Fry. Alan Turing. 29 Mar. 1951. National Portrait Gallery, www.npg.org.uk/collections/search/portrait/mw165875/Alan-Turing?LinkID=mp18700&role=sit&rNo=0. Accessed 3 Dec. 2019.

This image provided an image of Turing's face. Thus, this image was placed on the home page of the website.

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An ENIGMA Machine, Second World War, n.d., Thinking Machines

This is a black and white photograph of the Enimga machine itself. Its scramblers like the plugboard and rotor are visible.

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Erwin Rommel and Hitler. getty images, 17 Mar. 1943, www.gettyimages.co.nz/detail/news-photo/erwin-rommel-1891-1944-officer-field-marshal-germany-news-photo/548808111. Accessed 6 Feb. 2020.

This is a black and white image of Hitler and Rommel, a German general, conversing. This image is significant because it provided a visual of a significant figure in the North African Campaign which, with the help of Bletchley Park technology, was won by the Allies because they were provided with sufficient decripted information (Ultra).

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Hodges, Andrew. "Alan Turing: The Enigma." Turing.org.uk, www.turing.org.uk/scrapbook/ww2.html. Accessed 1 Feb. 2020.

Andrew Hodges, author of Alan Turing: The Enigma maintains this website completely dedicated to Alan Turing. It includes document transcripts and photographs which were extremely useful to read through and gather informaton/photos, tertiary and otherwise.

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"Joy Aylard - Film 4." Legasee.org.uk, Netfrux Technologies, www.legasee.org.uk/veteran/joy-aylard/. Accessed 2 Feb. 2020.

This video clip from veteran interview archive Legasee featured Joy Aylard, a WRNS bombe operator at Bletchly Park. She goes into detail of her times there, and she provided a descriptive explanation of how a bombe was operated and how extensively the machines were be utilized.

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Keystone Getty Images. Sea Convoy. 15 Nov. 1941. Churchill Archives, www.churchillarchiveforschools.com/themes/the-themes/key-events-and-developments-in-world-history/was-churchill-really-worried-about-the-battle-of-the-atlantic-and-if-so-why/background-information. Accessed 2 Feb. 2020.

This black and white image provides a visual of an aerial view of the different U-boats in the Battle of the Atlantic from the perspective of a US plane.

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Lieutenant General Bernard Montgomery, GOC V Corps, with war correspondents during a large-scale exercise in Southern Command, March 1941. Imperial War Museum, Mar. 1941, media.iwm.org.uk/ciim5/40/383/large_000000.jpg. Accessed 6 Feb. 2020.

The image provides a visual of Bernard Montgomery, a British military leader, in the North African campaign drove back Axis powers from Egypt.

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Mans, James. Alan Turing's Office in Hut 8, Bletchley Park.

This photograph depicts Alan Turing's workspace and desk in Hut 8, Bletchley Park. The preserved messiness must be a tribute to his disorganized habits.

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Mulligan, Timothy. "The German Navy Evaluates Its Cryptographic Security, October 1941." Military Affairs, vol. 49, no. 2, 1985, pp. 75–79. JSTOR, www.jstor.org/stable/1988402. Accessed 2 Feb. 2020.

Mulligan's journal exhibited a very intriguing conversation between two German prisoners of war, recorded by British interrogators. They chat about the impossibility of Britain ever cracking their unbreakable naval code. Interestingly enough, one of them argues that expert mathematicians might be able to decipher it in two years. Little did they know, Bletchley Park would soon emerge triumphant from their 4-rotor blackout not long after only to continue deciphering German Enimga naval ciphers.

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National Museum of Computing. image of bletchley park. culture24.org, www.culture24.org.uk/science-and-nature/technology/ART308790. Accessed 8 Feb. 2020.

This is a black and white photo of Bletchley Park estate - where codebreakers would intensely work day and night to crack German Enigma ciphers.

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Passport Sized Photograph of AMT. Turingarchive.org, www.turingarchive.org/viewer/?id=526&title=11

This image portrays Alan Turing's head and shoulders from a side view, laughing with a smile.

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Passport Sized Photograph of AMT. Turingarchive.org, www.turingarchive.org/viewer/?id=526&title=13.

This image portrays Alan Turing's head and shoulders from a side view, looking past the camera. His age is unknown when the photo was taken.

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​​​​​​​Technical University of Denmark. Images of the Enigma Machine parts and from different angles. The Matematik sider, matematiksider.dk/enigma_dtu_eng.html. Accessed 7 Feb. 2020.

This website contributed several images of the different parts of the machine itself. It provided up-close images of the plugboard, several rotors, and reflectors, as well as the entire machine. This website was crucial in providing visuals of the different parts of the Enigma machine which would be difficult to reflect with only words.

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Turing, Alan. "Turing's Treatise on the Enigma." 1940.

This typescript, authored by Alan Turing, provided an excellent source of data regarding the methods he and his colleagues at Bletchley Park had used to break into the German Enigma. It includesdhis hand-written diagrams and notes, despite their poor legibility.

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Turing, Alan Mathison. Turing's drawn diagram of his examination of the 25-letter Enigma cipher text with its crib. PDF file, 1940.

This picture portrays Turing's (messy) diagram of an Enigma cipher-text with its crib. His diagram illustrates the hard and complex math codebreakers had to do every day for their work.

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U-BOATS: Breaking the Enigma Code Allowed Brit Ships to Evade German U-boats. Alan Turing Father of Modern Computer Science, vixra.org/pdf/1903.0415v1.pdf. Accessed 2 Feb. 2020.

This image shows a surfacing German U-boat. Many like this one were used to sink thousands of military and merchant Allied ships. These German ships would have sent countless messages to other German military troops.

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U.S. Air Force. P-40s at their airbase in Egypt. NATIONAL MUSEUM OF THE UNITED STATES AIR FORCE, Oct. 1942, www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/196187/north-africa/. Accessed 6 Feb. 2020.

This black and white image provides a visual of the planes during the North African Campaign.

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Winston Churchill Archives Trust. Extract from the British government's weekly summary of the military situation in August 1940. Aug. 1940. Churchill Archives, www.churchillarchiveforschools.com/themes/the-themes/key-events-and-developments-in-world-history/was-churchill-really-worried-about-the-battle-of-the-atlantic-and-if-so-why/the-sources/source-3. Accessed 2 Feb. 2020. ​​​​​​​

This document is from the British government’s summaries of military situations during August 1940. It states the damages and the urgent problems regarding naval U-boat situations - what worried Winston Churchill immensely.


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Secondary Sources


"Alan Turing." Bl.uk, British Library, www.bl.uk/people/alan-turing. Accessed 2 Feb. 2020.

This web page from the British Library provided a number of interesting facts on Alan Turing, including his headmistress' comment on his genius when he was nine, setting him apart from the other students.

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Alan Turing, Enigma, and the Breaking of German Machine Ciphers in World War II. 31 Dec. 1997, www.archives.gov/files/publications/prologue/1997/fall/turing.pdf. Accessed 1 Jan. 2020.

Available to be read in its entirety on Google Play, "Prologue, The Journal of the National Archives" contained a section devoted to Alan Turing and the Enigma. It was extremely comprehensive and factual. It provided some excellent quotes and insights into important events and concepts such as the bombe and the mechanization of human intelligence both, of which are crucial ideas.

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Alvarez, D. E-mail interview. 3 Feb. 2020.

This email interview provided a specific example from a reliable source of the important effect of the bombe machine in a the war. It helped us to understand just how large the bombe's role was on World War II. Mr. Alvarez is a diplomatic cryptanalysist.

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Ambrose, Stephen E. "Eisenhower and the Intelligence Community in World War II." Journal of Contemporary History, vol. 16, no. 1, Jan. 1981, pp. 153-64. JSTOR, www.jstor.org/stable/260621?read-now=1&seq=2#page_scan_tab_contents. Accessed 1 Dec. 2019.

This quote from Lt. Taylor served as a great source information on it was supremely easy to rely too heavily on Ultra intelligence in turn, because of how quickly it was coming in via technology over human work. Though not used in-website very predominantly, the journal also covered how Eisenhower reacted to the British discovery at Bletchley Park. He was positive and commented on how it saves thousands of lives.

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Bateman, Gary M. "THE ENIGMA CIPHER Machine." American Intelligence Journal, vol. 5, no. 2, 1983, pp. 6–11. JSTOR, www.jstor.org/stable/44326071. Accessed 2 Feb. 2020.

Gary M. Bateman's journal on the Enigma cipher machine contained very quotable details on the aid that Ultra information provided for the Allied caused. Though sometimes waxing lyrical in his praise for the Turing bombe, Professor Jozef Garlinski offered a number of insightful words on such topics.

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Batey, Mavis. "Spying Out the Future." Historic Gardens Review, no. 24, 2010, pp. 6–10. JSTOR, www.jstor.org/stable/44791108.

Maevis Batey's journal article on Bletchley Park gave some particularly amusing insights into Turing's antisocial ways. This source also exhibited a number of photographs of Bletchley Park estate, showing off its beauty and seclusion.

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"Bletchley Park reveals Decrypted Nazi D-Day messages." Bbc.com, BBC News Services, 6 June 2019, www.bbc.com/news/uk-england-beds-bucks-herts-48530228. Accessed 8 Jan. 2020.

This BBC article explains the Germans forces' confusion in regards to the Allies' D-Day deception operation, having leaked the false information that the invasion target was Calais. One photograph depicts women working hard at decrypting messages in Hut 6 in Bletchley while another is a picture of a German intercepted message referencing the Allies' deception.

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Bomba Kryptologiczna. Cryptomuseum.com, www.cryptomuseum.com/crypto/bombe/img/bomba_full.jpg. Accessed 29 Jan. 2020.

This diagram depicts Rejewski's Polish bomba, which would later be improved upon by Turing to create the bombe. Comparatively, the Polish bomba is much more mechanically simpler and smaller.

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"Breaking the Code: From the Play Breaking the Code, by Hugh Whitemore: Act II, Scene 7." Bulletin of the American Academy of Arts and Sciences, vol. 64, no. 4, 2011, pp. 22–30. JSTOR, www.jstor.org/stable/23209130.

This journal article contained useful commentaries on Turing and Bletchey's efforts that especially emphasized the point that during this time, machines were used to solve human problems. This parallels the modern digital-electronical-computer age where most vital technology today is electrical.

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Budiansky, Stephen. Battle of wits : The Complete Story of Codebreaking in World War II. New York, Touchstone Book, 2002.

Providing several useful passages that were essential to our argument, this book by Stephen Budiansky was perhaps one of the most comprehensive accounts of the Enigma codebreaking in WWII. It explains the evolution of the bomba to the bombe and how the Allies rose to the challenge of creating this new technology under pressures of war and the desperation to break German Enigma ciphers to gain war intelligence. It especially emphasized the effects of breaking German ciphers in stopping German general Rommel in the North African Campaign, the U-boat attacks on Britain's supply convoys in the long Battle of the Atlantic, and Britain's preservation of the deception of D-Day.

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Copeland, Jack. "Alan Turing: The Codebreaker Who Saved 'Millions of Lives.'" BBC [Christchurch], 19 June 2012. BBC, www.bbc.com/news/technology-18419691. Accessed 29 Nov. 2019.

This source describes the effect of Alan Turing's contributions to cracking the Enigma code. It provides pictures as well as a quote from Winston Churchill. This source also describes the specific form of Enigma Code which Alan Cracked: the German U-boat cipher.

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Copeland, Jack B., editor. The Essential Turing. PDF ed., Oxford, Oxford UP, 2004.

Copeland's extremely in-depth writings on computing and AI in regards to the Enigma, clearly convey why Turing is called the father of computer science. It contained concise information on computer science concepts that, while they did not necessarily fully pertain to the argument at hand, were very interesting to read through. Copeland's guide to Turing's proof "On Computable Numbers" was however, useful, giving insight into Turing's thought process regarding how computers "think" and analyze data.

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Crypto Museum. "History of the Enigma." CryptoMuseum.com, edited by Crypto Museum, Crypto Museum, 27 Jan. 2019, www.cryptomuseum.com/crypto/enigma/hist.htm. Accessed 12 Nov. 2019.

This document provided a general contextualization and rundown of the process and contributing factors by which the code of the Enigma was cracked. It provided keen incites about the polish breakthrough, political factors, and the long term importance of the enigma machine. This document also provided significant time stamps.

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Destroyer Escort Historical Museum. "Destroyer Escorts in the Atlantic." Ussslater, www.ussslater.org/history/dehistory/history_atlanticbattle.html. Accessed 6 Jan. 2020.

Provided significant information about the U boats and the role of the enigma machine which gives some context as to what happened before. The document provided timestamps in the Battle of the Atlantic in which the efforts of the allies and the Bombe helped aide the allies in the war. This document also provides the names of the different significant U-boats that were active in the Battle such as the German submarine U-505.

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"Enigma" ["Enigma"]. Enigma.umww.pl, Ministry of Foreign Affairs of the Republic of Poland, 2017, enigma.umww.pl/en/. Accessed Dec. 2019.

This website was extremely informative, containing in-depth information on the Polish mathematicians to detailed steps in the cracking of the Enigma code. What was ultimately fascinating about this site is that it was originally made in Polish. It's quite clear at a glance that the site is heavily focused on the Polish efforts in cracking the Enimga. This is interesting because a British website most likely would have contributed the breaking of the Enigma code more so to British figures like Turing and Welchman. Because of this, further insights into Polish code efforts were gleaned, which may not have been present in other non-Polish sites. The detailed timeline along with the exhibited video, helped in comprehending the chronology of the breaking of the Enigma.

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"Enter Turing and Welchman." Bombe.org.uk, www.bombe.org.uk/enter-turing-and-welchman/.

This short article gave a brief description of Turing and Welchman's work on the bombe: Turing's innovation and Welchman's improvement on his bombe, which maximized code exploitations and reduce the need of obtaining loops in the crib and cipher-text pairing. A short quote was useful; it described Turing's reaction and approval at Welchman's design of "the diagonal board."

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"The Front Panel of a Bombe." Ellsbury.com, www.ellsbury.com/bombe/fig_2-1_frontpanel.gif.

This simple diagram depicts the front panel of the bombe made by Alan Turing. It shows the rotating drums and the speed of their rotation in analyzing German Enigma text.

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"Gordon Welchman Codebreaker." Crypto Museum, 19 Apr. 2018, www.cryptomuseum.com/people/gordon_welchman.htm. Accessed 3 Jan. 2020.

This source narrates the life of a coworker of Alan Turing. Gordon Welchman helped break codes in hut six of Bletchley park. This website provides a look at the kind of people to assist in the code breaking at Bletchley park.

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Hodges, Andrew. Alan Turing - the Enigma. Princeton, New Jersey, Oxford : Princeton UP, 2014.

This 736 page book proved to be a comprehensive read and an excellent narrative of the life of Alan Turing from his birth to his legacy after his tragic suicide. The book also explains how Turing's work at Bletchley was directly related to his leading role in breaking the German Enigma ciphers. Through his bombe machine, he facilitated a swifter and much more efficient way of decoding Enigma messages, enabling Allies to read secret German information. This was especially critical to the successes of battles such as the North African Campaign, the long Battle of the Atlantic, and D-Day. Especially useful and interesting was Hodges explanations of the functions of the Enigma machine. The helpful diagrams and thorough details provided an invaluable understanding to its mechanical operations.

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"The Inner Workings of an Enigma Machine." The Perimeter Institute of Theoretical Physics, uploaded by James Grime, 23 June 2014, www.youtube.com/watch?v=mcX7iO_XCFA. Accessed 1 Dec. 2019.

The video gives a thorough explanation and a thorough rundown on how the Enigma machine works, how the Germans used it, and why cracking the code was so difficult. The video provides step by step logistical parts as to how the different boards and sections of the machine works. It was not used toward the website's media.

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The International Value of Bletchley Park. Historicengland.org.uk, historicengland.org.uk/images-books/publications/national-international-value-bletchley-park/bletchley-values-paper/. Accessed 2 Feb. 2020.

This report truly discussed the international value of Bletchley Park. Especially useful was its emphasis on how the work there established foundations of the digital age and how technology was utilized on a methodical reasoning to regulate the obtention of information.

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Kahn, David. Seizing the Enigma : The Race to Break the German U-Boat Codes, 1939-1943. Boston, Houghton Mifflin, 1991.

This book by David Kahn served to be an excellent source of passages regarding the use of the bombe in the Battle of the Atlantic and the "pinchings," or Enigma codebook stealings, from the German U-boat U-559 which facilitated the lift of Bletchley's fourth-rotor naval Enigma blackout. Thus aiding Allied causes in the Battle because Bletchley regained the ability to decipher messages again. It describes the struggle of Allied convoys avoiding German U-boats and unfortunately sinking on account of them. Because of this, these convoys were unable to ferry supplies between shores such as Britain and America. Kahn seems to tell his story like a race - a race to break the code and begin winning the Battle fo the Atlantic.

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Lendl, Christian. Bletchley Park British Cryptanalysis during World War II. www.bletchleypark.at/ebooks/ChristianLendl_BletchleyParkHQ.pdf. Accessed 2 Feb. 2020.

This PDF book helped define words used in the website. It gives an account of the effects of the Enigma and its complited communications on Allied efforts in WWII and what happened during the process in breaking Enigma.

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Lycett, Andrew. "Breaking Germany's Enigma Code." British Broadcasting Corporation, 17 Feb. 2011, www.bbc.co.uk/history/worldwars/wwtwo/enigma_01.shtml. Accessed 6 Jan. 2020.

This webpage provided significant information about the impact of Bletchley Park in cracking the ciphers. It gave parts of a timeline which helped with the understanding of chronological significances as well as the motivations for the British to invent a solution. Primarily, this website sparked a few ideas as to where to direct some attentions ny means of keyword. For example, the submarine battles and U boats of the Germans and the British were therefor more deeply researched.

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Mead, Richard. The Men Behind Monty. Barnsley, Pen & Sword Military, 2015.

Upon researching the North African Campaign and the role of Lt. Gen. Montgomery "Monty," this book by Richard Mead became more of a side book, outside of current research. It described the leadership styles of "Monty." It covered his campaigns in North Africa, Sicily, Italy, and more. However, this book contained an interesting quote by E.T. Williams about the over reliance of British military on Ultra information, which was gained from machines such as Turing's bombe. This demonstrates the dependency of man on machines, in this case, in gaining military (Ultra) information.

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"The Polish Breakdown of Enigma." Macs.hw.ac.uk, www.macs.hw.ac.uk/~foss/valentin/Polish_breackdown.html. Accessed 4 Dec. 2019.

This website provided a useful explanation of Rejewski's "card catalog" which was used to compare patterns and decode messages in the Enigma code before the Germans changed their Enigma settings, in addition to the later-used perforated sheets, or "Zygalski sheets."

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Powell, Lewis F., and Diane T. Putney. ULTRA and the Army Air Forces in World War II : An Interview with Associate Justice of the U.S. Supreme Court Lewis F. Powell, Jr. Honolulu, UP of the Pacific, 2005.

This book, while not used too much elsewhere, contained a descriptive quote from General Eisenhower on Ultra intelligence, how it simplified his strategic work, and how it potentially saved millions of lives - British and American. It was an interesting read otherwise.

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Russell, Jerry. "SRH-142 ULTRA AND THE CAMPAIGN AGAINST THE U-BOATS IN WORLD WAR II." Naval History and Heritage Command, 20 May 1980, www.history.navy.mil/research/library/online-reading-room/title-list-alphabetically/u/current-doctrine-submarines-usf-25-a.html. Accessed 30 Jan. 2020.

This document was used after looking through several other sources to find keywords. This document provides a more specific timeline of what happened in the Battle of the Atlantic and the involvement of the US. This document provided great incites on the importance of destroying the German U-Boats and the necessity of discovering the Enigma codes in order to find out the location of the U-Boats. Additionally, this document provided important dates or periods of time that were significant in the Battle of the Atlantic.

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Sebag-Montefiore, Hugh. Enigma: Battle for the Code. London, Weidenfeld & Nicolson, 2001.

Sebag-Montefiore's book turned out to be a really extensive view of the cipher breaking effort, describing Bletchley Park and equally important measures elsewhere in Poland. The book contained several descriptive passages describing the Enigma machine scramblers, including the rotors and plugboard. A very informative diagram of the Enigma machine was one of its most helpful visuals.

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Smith, Michael, and Ralph Erksine, editors. Action this Day : Bletchley Park : From the Breaking of Enigma to the Birth of the Modern Computer. London, Bantam, 2002.

Responding to a letter by four British codebreakers - Turing included - explaining that Bletchley's efforts in breaking the Enigma code were being hindered by lack of funds, Churchill ordered they be given all that they needed. He titled his response of his decision with the words "ACTION THIS DAY." This insightful book included discourses by a number of British leading historians and former codebreakers. It also gave a detailed history of Bletchley Park. The contributors traced Bletchley's legacy, from the barrier-breaking work of the bombe which lead to the breaking of Enigma, to even the invention of modern computing. Especially helpful was a table-chart displaying what ciphers the bombes had cracked and how long it took for each.

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Taylor, Telford. Early "E" History. Edited by Frode Weierud, 22 Jan. 1944. Cryptocellar.org, cryptocellar.org/Enigma/ttaylor.pdf. Accessed 27 Jan. 2020.

This report document gave a brief description of the status of the general GC+GS work on Enigma traffic. It went on to describe Denniston and Knox's interaction with the Poles and their meeting discussing the Poles' successes in their efforts to break the Enigma cipher. It states that while Poland had been invaded Germany, many codebreakers remained strong, and some escaped to other countries.

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"Tackling Enigma (Turing's Enigma Problem Part 2) - Computerphile."Youtube.com, YouTube, 9 Dec. 2014, www.youtube.com/watch?v=kj_7Jc1mS9k. Accessed 6 Apr. 2020.

This media clip used in-site was edited from a YouTube video by the channel "Computerphile," featuring Professor David Brailsford - a teacher at the School of Computer Science and Information Technology of the University of Nottingham. In this video, he explains the complexities of the Turing bombe and Turing's thinking behind the Enigma, having based his invention off previous Polish work. Professor Brailesford offered a number of deeper insights and a learned experience with the inner and technical working of the bombe machine itself from describing its "drums" to its "menus." He even pointed out Enigma's greater ciphertext weaknesses.

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​​​​​​​"Who Were the Real Enigma Heroes?" Thehistorypress.co.uk, History Press, www.thehistorypress.co.uk/articles/who-were-the-real-enigma-heroes/. Accessed 1 Feb. 2020.

This article provided a detailed narrative on the brave act of Fasson and Grazier - the two men who retrieved German Enigma information from U-559 and lost their lives in the process. It portrays both of their portraits. They will be forever remembered.

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