A manual called "Camp Delta Standard Operating Procedure" (SOP), dated 28 February 2003, and designated "Unclassified//For Official Use Only", was published on WikiLeaks. This is the main document for the operation of Guantánamo Bay, including the securing and treatment of detainees. The 238-page document includes procedures for identity cards and 'Muslim burial'. It is signed by Major General Geoffrey D. Miller. The document is the subject of an ongoing legal action by the American Civil Liberties Union (ACLU), which has been trying to obtain it from the Department of Defense. On 2 July 2008, The New York Times revealed that the U.S. military trainers who came to Guantánamo Bay in December 2002 had based an entire interrogation class on a chart copied directly from a 1957 Air Force study of "Chinese Communist" interrogation methodology (commonly referred to as 'brainwashing') that the United States alleged were used during the Korean War to obtain confessions. The chart showed the effects of "coercive management techniques" for possible use on prisoners, including "sleep deprivation", "prolonged constraint" (also known as "stress positions") and "exposure". The chart was copied from a 1957 article (entitled "Communist Attempts to Elicit False Confessions From Air Force Prisoners of War") written by Albert D. Biderman, working as a sociologist for the Air Force. Biderman had interviewed American prisoners of war returning from Korea who had confessed to having taken part in biological warfare or involvement in other atrocities. His article sets out that the most common interrogation method used by the Chinese was to indirectly subject a prisoner to extended periods of what would initially be minor discomfort. As an example, prisoners would be required to stand for extended periods, sometimes in a cold environment. Prolonged standing and exposure to cold are an accepted technique used by the American military and the CIA to interrogate prisoners whom the United States classifies as "unlawful combatants" (spies and saboteurs in wartime, "terrorists" in unconventional conflicts) although it is classified as torture under the Geneva Conventions. The chart reflects an "extreme model" created by Biderman to help in "understanding what occurred apart from the extent to which it was realized in actuality" (Biderman did not have a PhD in Sociology [usually the minimum qualification required to carry out such work] and the underlying research was not subjected to peer-review). His chart sets out in summary bullet points the techniques allegedly used by the