User:SchmiAlf/German influence

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During World War II Nazi Germany developed rocket technology that was more advanced than that of the Allies and a race commenced between the Soviet Union and the United States to capture and exploit the technology. Soviet rocket specialist were sent to Germany in 1945 to obtain V-2 rockets and worked with German specialists in Germany and later in the Soviet Union to understand and replicate the rocket technology. The involvement of German scientists and engineers was an essential catalyst to early Soviet efforts. In 1945 to 1947 the use of German expertise was invaluable in reducing the time needed to master the intricacies of the V-2 rocket, establishing production of the R-1 rocket based on locally available materials. In 1948 to 1949 it was used for developping concept studies for long-range and intercontinental ballistic missiles.

Background[edit]

V-2 rocket launching, Peenemünde, on the north-east Baltic German coast. (1943)

During WWII Nazi Germany developed the world's first liquid-propellant rockets known as the V-2, with the technical name A4. The missile was developed as a "vengeance weapon" and assigned to attack Allied cities as retaliation for the Allied bombings against German cities.[1] The V-2 rocket also became the first artificial object to travel into space by crossing the Kármán line with the vertical launch of MW 18014 to a vertex of 174.6 km on 20 June 1944.[2]

The V-2 rocket was far more advanced than any rocket developed by the Allies. Prior to 1945 the United Kingdom, United States and Soviet Union had not developed a rocket with a thrust greater than 1.5 metric tons, whilst the V-2's thrust was up to 27 metric tons.[3] A race commenced between the Allies, particularly United States and Soviets, to acquire the technology behind the V-2 and similar weapons developed by Nazi Germany.[4]

At the end of WWII the Soviet Union had been devastated by Nazi Germany, with 27 million people killed, 1,700 cities destroyed and agriculture production reduced to famine proportions.[5] At the Yalta Conference Winston Churchill, Franklin D. Roosevelt, and Joseph Stalin agreed that war reparations were payable by Nazi Germany in the form of equipment, goods and German labour, with the Roosevelt and Stalin agreeing to an amount of $20 Billion, with 50% ($10 Billion) going to the Soviet Union.[6][7] The Soviets, United States and to a lesser extent British and France all seized "intellectual" repatriations from Germany.[8] The dismantling of German industry also ensured the complete disarmanent of its war potential,[9] as agreed at the Potsdam Conference.[10]

Soviet rocket development prior to 1945[edit]

Rocketry in the Soviet Union began in 1921 with extensive work at the Gas Dynamics Laboratory (GDL), which was merged with the Group for the Study of Reactive Motion (GIRD), lead by Sergey Korolev, in 1933 to form the Reactive Scientific Research Institute (RNII).[11] This well-funded and staffed laboratory created the Katyusha rocket launcher[12] and built over 100 experimental rocket engines under the direction of Valentin Glushko. Design work included regenerative cooling, hypergolic propellant ignition, and swirling and bi-propellant mixing fuel injectors. During the early 1930s Soviet rocket technology was comparable to Germany's,[13] but Joseph Stalin's Great Purge severely damaged its progress, with Korolev, Glushko and many other leading engineers imprisoned in the Gulag.[14]

The Soviet Union was first informed of the Nazi Germany's rocket programme in July 1944 by Winston Churchill, who appealed directly to Stalin to inspect a missile test station in Debica, Poland which was about to be overrun by advancing Soviet forces. British and Soviet personnel inspected the site and recovered A4 missile parts, which were sent to London via Moscow.[15] Whilst in Moscow the parts were inspected by several members of the Soviet rocket design bureau RNII.[16]

Work in Eastern Germany[edit]

Institut Rabe and Büro Gröttrup[edit]

In early 1945 a team of Soviet rocket specialists were sent to Germany to identify and recover German rocket technology.[17] The first Soviet team to arrive at Nordhausen, the main V-2 construction site, were disappointed, United States teams had already removed approximately 100 completed V-2 missiles and destroyed what remained. In addition, as part of the Operation Paperclip more than 500 leading German rocket engineers had surrendered to the United States, including 15 tons of documents relating to rocket technology.[4][18]

Soviet search teams did locate V-2 parts at the Mittelwerk underground rocket factory near Nordhausen, at Lehesten (test site for rocket engines) and other locations in the Thuringia area. Therefore, a Soviet missile research group based in Bleicherode was created in July 1945 led by Boris Chertok and called Institut RABE that recruited and employed German rocket specialists to work with Soviet engineers for restoring a working V-2 rocket flight control system.[19] The Institut RABE was also created with the purpose of retrieving German rocket specialists from the United States Occupation zone. As an early success in August 1945 Chertok recruited Helmut Gröttrup (the deputy for the electrical system and missile control at Peenemünde, also assistant to Ernst Steinhoff) from American territory, along with his family, and offered him founding the Büro Gröttrup[20] in parallel to the Institut RABE.[21]

Institut Nordhausen and Zentralwerke[edit]

In February 1946 the Institute RABE and Büro Gröttrup were absorbed into the larger Institut Nordhausen,[22] which had the goal of recreating the entire German A4 rocket technology. It was headed by Korolew as the Chief Engineer and Gröttrup as the German head.[23] In May 1946, the Institute Nordhausen, Institute Berlin (reconstructing the Wasserfall missile) and several manufacturing sites in Thuringia (until 1945 part of the Mittelwerk supply) were combined into the Zentralwerke.[24] By October 1946, Zentralwerke employed 733 Soviet specialists, and between 5,000 and 7,000 Germans, including Korolev as Chief Engineer, Glushko as head of Engine assembly and propulsion systems, and Gröttrup as General Director.[19]

Operation Osoaviakhim[edit]

On 13 May 1946 USSR Council of Ministers Decree No 1017-419 'Questions on Reactive Armaments' was signed by Stalin, which established the future strategy and direction for Soviet rocketry. Among the detailed requirements was that work in Germany would end in late 1946 with Soviet and German personnel transferred to Soviet locations. Therefore, the most capable German rocket scientists and engineers were identified, and on 22 October 152 personnel and their families (a total of 495 persons) were deported to the Soviet Union as part of Operation Osoaviakhim together with more than 2,000 other German specialists.[25][26][27] According to another source, 2,552 German specialists together with 4,008 family members were relocated to the USSR, 302 of them having knowledge in rocketry, thereof 198 from the Zentralwerke.[28]

Work in the USSR[edit]

Soviet R-1 on Vidal carrier (1948)

On arrival the 302 Germans were split into several groups. A large group of 99 specialists from the Zentralwerke was installed in Podlipki in the north east section of Moscow as part of Korolev's NII-88, 76 design engineers were transferred to Gorodomlya Island, and 23 specialists to Khimki, northwest of Moscow, as part of Glushko's OKB-456 for the development of rocket engines.[28]

Initial technology transfer until end of 1947[edit]

According to Chertok, the initial work included:[29]

  • "consultations for issuing a set of A4 rocket documentation in Russian,
  • compiling diagrams of the A4 and surface-to-air guided missile research laboratories,
  • studying issues related to boosting the A4 rocket engine,
  • developing the design for an engine with a thrust of 100 tons, and
  • preparing to assemble rockets that were made of German parts and had been outfitted with equipment at the Institute Nordhausen."

In addition, the then Soviet Minister of Armaments Dmitry Ustinov reported the following tasks for 1947:[30]

  • "performing individual theoretical computation work in aerodynamics and ballistics,
  • participation in laboratory and bench tests of assemblies and units,
  • the installation and adjustment of special technological equipment and apparatuses which have arrived from Germany."

The ministry for production of telecommunications assigned another group of 43 German scientists to assist NII-885 under the Chief Designer of autonomous control systems Nikolay Pilyugin for developing gyroscopic guidance systems.[28]

While located in the Soviet Union the German specialists received fairly high wages and good conditions, which were mainly based on their qualifications. For example, Gröttrup was initially paid 7,000 rubles per month[31] and his family were housed in a six-room villa and provided with a chauffeured vehicle. The average wage received by a German graduate engineer was 4,000 rubles per month, plus all Germans were entitled to performance bonuses. As a comparison, Chertok, the former head of Institute Rabe and now Deputy Chief Engineer and Head of department for guidance systems, who also now supervised the German specialists working on control systems, received a salary of 3,000 rubles per month and his family lived in two rooms of a communal four-room apartment.[32][33]

Drawing of the Soviet R-1 missile, NATO code SS-1 Scunner

The first Soviet tests of V-2 rockets took place in October 1947 at Kapustin Yar. 13 German engineers participated in the tests, among them Helmut Gröttrup, Johannes Hoch, Kurt Magnus, Fritz Viebach, Hans Vilter, Waldemar Wolff.[34] The first two rockets were successfully launched and flew for approximately 200 km, however they deviated 30 km and 180 km from their intended target. The German specialists Magnus and Hoch were instrumental in resolving the issue, which was an unknown problem with the V-2 rockets recovered from Germany.[35]: p. 123-135  For resolving the issue all the 13 German specialists were each rewarded with a large 15,000 ruble bonus.[36][37]

In June 1947 the German team in NII-88, led by Gröttrup, proposed the development of an improved version of the V-2, which he called the G-1 (R-10 in Soviet terms).[38] This plan, whilst supported by Ustinov and senior Soviet management, was opposed by Soviet engineers, particularly by Korolev, who was now Chief Designer of long-range ballistic missiles. Korolev had simultaneously and independently commenced work on the Soviet copy of the V-2, designated as R-1, and an improved R-2 for doubled shooting range. Some Soviet engineers of NII-88 were deputized to support the Germans in calculations for G-1 which delayed Korolev's progress.[39][40][41]

Work at OKB-456 for rocket engines[edit]

Glushko, who was now Chief Designer of liquid-propellant rocket engines in OKB-456 in Khimki, used the expertise of 23 German engineers and technicians under the lead of Werner Baum, a Peenemünde engine expert. The Germans had no contact to the German team at NII-88 and had the initial task of mastering and improving the existing V-2 engine, internally called RD-100 (copy of V-2 engine) and RD-101 (used for R-1) with a thrust of up to 267 kN. In 1948 and 1949 they participated in the KS-50 ("Lilliput")[42] design and tests for improved thermal design and nozzle concepts for higher combustion pressure and efficiency. In 1949 initial tests of the experimental ED-140[43] to burn liquid oxygen with kerosene fuel at a pressure of 60 atm were carried out.[44] The development of the RD-110 engine[45] with a thrust of 120 tons was started in 1947 but discontinued after 1949.[46] Due to lack of dedicated Russian history, it is disputed how much the German team contributed to these initial developments.[47]

By September 1950, the 23 strong German team was sent back to Germany.[48]

Work on Gorodomlya Island in 1948 and 1949[edit]

Due to political and security concerns, German specialists were not allowed direct knowledge or access to any Soviet missile design.[49][50] Therefore, once the Soviets had mastered understanding and production of the V-2 rocket in 1946–47, all German specialists were excluded from Soviet developments.[51] Their work was conducted independently, including work on the G-1, which proceeded as a "draft plan".[52]

Until early 1948 all German specialists working in Podlipki were transferred to Gorodomlya Island. In September 1948 test flights were carried on the R-1, the Soviet copy of the V-2 rocket, built with local materials. No German personnel were present for these tests at Kapustin Yar.[53][54]

For 1948 Ustinov summarized the following German tasks:[30]

  • "A preliminary design of the R-10 rocket [German designation G-1] with a range of 800 km and a payload of 250 kg was developed and an initial concept [was developed] of the R-12 rocket [German designation G-2] with a range of 2500 km with a payload of one ton.
  • A number of new design elements were proposed in these designs, the principles of operation of which have been verified in experimental models.
  • A model of a research simulator was created for integrated processing of the rocket with a control system.
  • A number of sensors have been developed such as, for example: a fuel level sensor in the rocket’s tanks, a differential manometer with safety valves, a dynamometer thrust sensor, a summing gyroscope and an instrument to test it, different versions of dynamometers, etc."

In December 1948 the updated plan for the G-1 rocket was reviewed. The Soviet findings on the preliminary design study with improved accuracy and a largely extended target range of 810 km were "positive and amiable", with final approval by all Soviet groups as it "in terms of scope surpassed the requirements."[54] However major work on the G-1 was terminated by senior Soviet management to discontinue the parallel development in conflict with R-2 targets.[55]

For 1949 Ustinov summarized the following German tasks:[30]

  • "A preliminary design was developed of the R-14 [German designation G-4] rocket with a range of 3000 km and a payload of three tons and an initial concept of the R-15 [i.e., Sänger's intercontinental bomber, sometimes referred to as G-3 or G-5][56] with a range of 3000 km, a payload of three tons, and radio control.
  • The overall structural diagrams of the rocket are given in these rockets, theoretical computation work was done, and ways and methods were outlined to solve new individual control questions (the replacement of exhaust vanes of R-14 with a swiveling combustion chamber).
  • However, the continuation of this work seemed inadvisable as a consequence of the unwieldiness of the structures (the large dimensions), and a number of unsolved problems of aerodynamics and stabilization, the propellant feed, and other things.
  • The MU-2 simulator and the three-axis MU-3 simulator, which were used in NII-88, have been manufactured."

The R-14 and R-15 design tasks were personally commanded by Ustinov during a visit on Gorodomlya in April 1949.[57] These designs were carried out under extreme time pressure with sketches of layout drawings and evaluations of basic parameters. In addition, the Germans were not allowed to access results of strictly classified Soviet work for long-range missiles, and Soviet engineers were forbidden to talk about.[58] In October 1949 Korolev and Ustinov visited the branch of NII-88 in Gorodomlya to gather and understand German knowledge as much as possible for pushing the development of Soviet missiles.[57] The concept of the G-4 targeted to build a long-range ballistic missile for a range of 3000 km and a payload of 3 tons. The G-2's and G-4's shape of a circular cone was intended to ensure increased aerodynamic stability so that the stabilization surfaces at the rear could be dispensed with. The position control was carried out by a swiveling engine (gimbal design). At the same time, the German designers paid attention to radical simplification of the overall system and consistent weight savings in order to achieve the required reliability and range.[59][35]: p. 202-211 [60]

Work on Gorodomlya Island after 1949 and return to Germany[edit]

Due to the isolation, both technically and geographically, the German team felt increasingly discouraged and insisted on a definite date for their return to Germany. Severe conflicts arose because Gröttrup and his team refused to research on the use of hypergolic propellants as storable fuels for long-term readiness.[61] In April 1950 the Soviet Ministry of Armaments terminated further development on long-range missiles at Branch No. I of NII-88. The later studies were limited to initial designs, including diagrams and calculations. None of these studies were officially taken up by the Soviets. From early 1951 young Soviet engineers were sent to Gorodomlya Island for training purposes. By this time most of the German specialists were spending their time playing sports, gardening or reading technical literature.[62]

The return from Gorodomlya occurred in three waves in December 1951, June 1952, and the last group of twenty, including Gröttrup and Magnus, left in November 1953.[63] By the end of 1950 a small number of Germans (among them Johannes Hoch) were transferred to Moscow and worked on activities for surface-to-air missiles.[64]

Historical analysis[edit]

Historians have disagreed on the extent that Nazi Germany played with developing the Soviet rocket program. Chertok, who participated in the events and documented the details in his mammoth 4 volume Rockets and People said that the Germans had little influence and the R-7 rocket that propelled the Sputnik 1 to orbit was "free of the "birthmarks" of German rocket technology".[65] This view is supported by German born historian of rocketry Willey Ley, who wrote "In reality, the Germans did not build anything for the Russians, did not “supervise" the firings, and did not "introduce innovations".".[66][67]

Other historians, particularly German based, have claimed that German specialists had an extensive influence on Soviet rocketry. In particular Dr. Olaf Przybilski has pointed out similarities between later Soviet rockets and the studies carried out by German specialists,[68] however these claims lack convincing evidence.[69][67]

Asif Siddiqi, whose epic book Challenge to Apollo : the Soviet Union and the space race, 1945–1974 was rated by The Wall Street Journal as one of the best works on space exploration,[70] takes a more balanced approach by acknowledging Nazi Germany rocket technology and involvement of German scientists and engineers was an essential catalyst to early Soviet efforts. In 1945 and 1946 the use of German expertise was invaluable in reducing the time needed to master the intricacies of the V-2, establishing production of the R-1 rocket and enabling a base for further developments. However, due to a combination of reasons, including secrecy requirements due to the military nature of the work, political considerations and personal reasons from some key players, from 1947 the Soviets made very little use of German specialists. They were effectively frozen out from ongoing research and their influence on the future Soviet space program was marginal.[71][50][67][72] Siddiqi also noted a CIA report, which summed up the total German contribution as follows:

"The German scientists made a very valuable contribution to the Soviet missile program[;] however, it cannot be said that without the Germans the Soviet Union would have had no significant missile program....There is no doubt that it took the German war time success with guided missiles to cause Stalin and his colleagues to devote large scale support to the Soviet effort in this field. Once this support was forth coming the use of German scientists permitted the Soviets to achieve results in a much shorter time than it would have taken them along but there is no reason to believe that the Soviets could not have eventually done the job by themselves".[73]

References[edit]

  1. ^ Harvey, Ailsa (29 March 2022). "V2 rocket: Origin, history and spaceflight legacy". space.com. Archived from the original on 5 June 2022. Retrieved 28 June 2022.
  2. ^ Neufeld, Michael J. (1995). The Rocket and the Reich: Peenemünde and the Coming of the Ballistic Missile Era. New York: The Free Press. p. 158. ISBN 9780029228951.
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  4. ^ a b Siddiqi 2000, p. 24.
  5. ^ Siddiqi 2000, p. 23.
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  12. ^ Chertok 2005, p. 167 Vol 1.
  13. ^ Chertok 2005, p. 167-8 Vol 1.
  14. ^ Siddiqi 2000, p. 10-14.
  15. ^ Chertok 2005, p. 258-9 Vol 1.
  16. ^ Siddiqi 2000, p. 22.
  17. ^ Chertok 2005, p. 214 Vol 1.
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  19. ^ a b Zak, Anatoly. "Soviet rocket research in Germany after World War II". Russian Space Web. Archived from the original on 14 February 2016. Retrieved 28 June 2022.
  20. ^ Henze, Bernd; Hebestreit, Gunther (1998). Spuren der Vergangenheit: Raketen aus Bleicherode [Traces of the past - rockets from Bleicherode] (in German). Bleicherode: H & H-Verlag. p. 92. ISBN 978-3-00-003321-6. In August 1945 the Soviet search commands traced Helmut Gröttrup in Hessian Witzenhausen ... and enticed him with good offers to Bleicherode. On September 3, 1945, he started in a newly founded engineering office, initially separate from Institut RABE. From a letterhead the address of BÜRO GRÖTTRUP could be retrieved in Uthemannstraße 1, Bleicherode.
  21. ^ Антон Первушин, Антон (22 October 2020). "Секретный филиал на Городомле" [Secret branch on Gorodomlya] (in Russian). Retrieved 8 September 2023. At the Institute Rabe, Gröttrup was received with caution. He was rather dismissive of the team of German specialists who managed to gather there, speaking in favor of only the gyroscopicist Kurt Magnus and the electronics engineer Hans (Johannes) Hoch - he simply did not know the rest. In order not to inflame passions, it was decided to form a special "Büro Gröttrup", the first task of which was to compile a detailed report on Peenemünde rocket developments. It did this until mid-1946.
  22. ^ Hall, Peter (2011). "Institut Nordhausen" (in German). Retrieved 29 September 2022. In the subpage, Gröttrup is named as the head of Institut Nordhausen (1946)
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  24. ^ Uhl 2001, p. 98.
  25. ^ Zak, Anatoly. "Official decisions on the deportation of Germans". Russian Space Web. Retrieved 3 July 2022.
  26. ^ Siddiqi 2000, p. 37-42.
  27. ^ Hebestreit, Gunther. "Geheimoperation OSSAWiAKIM: Die Verschleppung deutscher Raketenwissenschaftler in die Sowjetunion" [Secret operation Ossawakim: The relocation of German rocket scientists into the Soviet Union]. Förderverein Institut RaBe e.V. Retrieved 29 September 2022. An order from Moscow was read to the people who had been awakened from their sleep, in which they were informed that the Zentralwerke were to be relocated to the Soviet Union, which affected both the facilities and equipment and the personnel.
  28. ^ a b c Uhl 2001, p. 132-133.
  29. ^ Chertok 2005, p. 45 Vol 2.
  30. ^ a b c Ustinov, Dmitry. "Memorandum of D. F. Ustinov to L. P. Beria on the Use of German Specialists". Retrieved 8 September 2023.
  31. ^ "Werk 88 (NII-88): Salary notification for Helmut Gröttrup" (in German). 29 December 1946. Retrieved 8 September 2023.
  32. ^ Siddiqi 2000, p. 45.
  33. ^ Chertok 2005, p. 44-46 Vol 2.
  34. ^ Uhl 2001, p. 152-159.
  35. ^ a b Magnus, Kurt (1993). Raketensklaven. Deutsche Forscher hinter rotem Stacheldraht [Rocket slaves: German research behind red barbwire] (in German). Stuttgart: Deutsche Verlagsanstalt. ISBN 978-3421066350.
  36. ^ Siddiqi 2000, p. 55-56.
  37. ^ Chertok 2005, p. 36-38 Vol 2.
  38. ^ Wade, Mark (2019). "G-1". Encyclopedia Astronautica.
  39. ^ Siddiqi 2000, p. 58.
  40. ^ Chertok 2005, p. 48-49 Vol 2.
  41. ^ Some of Chertok's comments on Korolev's relation to the German scientists are questionable. As an example, he falsely claims that Korolev had never visited Gorodomlya (p. 49 Vol 2).
  42. ^ "КС-50 "Лилипут" (KS-50 "Lilliput")". Retrieved 8 September 2023.
  43. ^ "ЭД-140 (ED-140)". Retrieved 8 September 2023.
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  45. ^ Wade, Mark (2019). "RD-110". Encyclopedia Astronautica.
  46. ^ "РД-110 (8Д55) (RD-110 (8D55)". Retrieved 8 September 2023.
  47. ^ Zak, Anatoly (5 August 2012). "End of German involvement at OKB-456". Retrieved 8 September 2023.
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  51. ^ Baker & Zak 2013, p. 13.
  52. ^ Siddiqi 2000, p. 58-60,83.
  53. ^ Siddiqi 2000, p. 60-61.
  54. ^ a b Chertok 2005, p. 128 Vol 2.
  55. ^ Siddiqi 2000, p. 63.
  56. ^ Wade, Mark (2019). "RD-110". Encyclopedia Astronautica.
  57. ^ a b Siddiqi 2000, p. 81.
  58. ^ Chertok 2005, p. 66 Vol 2.
  59. ^ Uhl 2001, p. 167-168.
  60. ^ Gröttrup, Helmut (1958-04). "Aus den Arbeiten des deutschen Raketen-Kollektivs in der Sowjet-Union" [On the work of the German rocketry collective in the USSR]. Raketentechnik und Raumfahrtforschung (in German) (2). Stuttgart: 58–62. Retrieved 2023-09-09. The most significant result of the German collective's work was the demonstration that it is possible to build ballistic missiles with a mass ratio of 0.1 allowing a payload fraction of 40% of empty weight, thus reaching medium-range distances using conventional propellants with a single-stage missile. Another corollary of ultra-lightweight cell design is the development of two-stage missiles in which only the first-stage engines are jettisoned, on which a number of projects have been worked out. {{cite journal}}: Check date values in: |date= (help)
  61. ^ Zak, Anatoly. "Long demise of the German collective". Russian Space Web. Retrieved 8 September 2023.
  62. ^ Siddiqi 2000, p. 63,81–82.
  63. ^ Chertok 2005, p. 69 Vol 2.
  64. ^ Siddiqi 2000, p. 82.
  65. ^ Chertok 2005, p. 73 Vol 2.
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  69. ^ Siddiqi, asif (2008). "Spaceflight in the National Imagination" (PDF). Remembering the Space Age. 4703: 22. Bibcode:2008NASSP4703...17S. Archived (PDF) from the original on 17 June 2022. Retrieved 2 July 2022.
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Sources cited[edit]