U.S.A national archives, O.S.S records RG 226, Entry 210, reports prepared by Dr Alexander S. Lipsett, June-August 1942, Information on Poland, with statement that “over 3,000 prisoners have died in the Polish concentration camp at Oswiecim (Auschwitz) during the past eight months
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K. G. Saur Verlag GmbH & Company, The End of the Holocaust, 1989, Walter de Gruyter| (ISBN9783110976519), p. 316–320. « Anderson put an end to the proposal: "I do not consider that the unfortunate Poles herded in these concentration camps would have their status improved by the destruction of the extermination chambers. There is also the possibility of some of the bombs landing on the prisoners as well, and in that event, the Germans would be provided with a fine alibi for any wholesale massacre that they might perpetrate. I therefore recommend that no encouragement be given to this project." Although Spaatz's officers had read Mann’s message reporting acceleration of extermination activities in the camps in Poland, they could perceive no advantage to the victims, in smashing the killing machinery. »
Dino Brugioni and Robert Poirier, The Holocaust revisited: A retrospective analysis of the Auschwitz-Birkenau extermination complex; CIA report 1978.
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Dino Brugioni, Auschwitz and Birkenau: Why the World War II photo interpreters failed to Identify the extermination complex, Military Intelligence, vol. 9, no 1 (jan.-mars 1983) : pages 50-55. Republished here
The U.K. National Archives, Daily proforma returns contained in GPCC series monthly reports, for ten concentration camps, 1942-1943 Daily proforma returns contained in GPCC German Police Concentration Camp series monthly reports, for ten concentration camps, including Auschwitz, Buchenwald and Dachau, include daily intakes and deaths, with inmate totals listed by nationality headed by Jews
