A tape from Air Force One recorded in the aftermath of John F Kennedy's assasination is among the highlights of Cowan's November 15 American History auction in Cincinnati.
The tape features the voices of Kennedy's chiefs of staff, with topics of discussion including the assassination, the wounding of Governor Connally and arrangements for transportation of Kennedy's body following touchdown in Washington.
The lot is valued at $40,000-60,000.
The open reel audiotape is two hours and 22 minutes long, and housed in the original White House Communications Agency box.
It features a label that reads: "Traffic involving AF-1 in flight from Dallas, Texas to Andrews AFB on November 22, 1963".
The tape is the only original copy in private hands, with the other donated to the National Archives in 2012.
It was discovered among the personal effects of General Chester "Ted" Clifton Junior, who was Kennedy's military aide and de facto chief of staff.
In the 1970s, an edited recording of the meeting was released to the public.
The original offered in the sale is 30 minutes longer and features more names and incidents - including attempts to locate Kennedy's political adversaries at the time of the assassination.
The sale at Cowan's will include a Polaroid photograph of the assassination, taken by Mary Ann Moorland at almost the exact moment that the first shot was fired.
We have a range of Kennedy memorabilia available, including this original poster from his 1960 presidential campaign - which saw him trump the incumbent vice-president Richard Nixon in a televised debate.
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