Published: Nov 15, 2011 3:44 PM EST

PHILADELPHIA (AP) - A long-lost version of Air Force One recordings made after President John F. Kennedy's assassination, with more than 30 minutes of additional material not in the official version in the government's archives, has been found and is for sale.
    
There are incidents and code names described on the newly discovered two-plus hour recording. It predates a shorter recording formerly thought to be the only surviving version.
    
The Raab Collection, a Philadelphia historic documents dealer, is selling the reel-to-reel tape for $500,000.
    
The tape comes from the estate of Army Gen. Chester "Ted" Clifton Jr., a Kennedy aide who was in the Dallas motorcade when the president was assassinated.
    
Clifton died in 1991. The Raab Collection acquired the items after the death of Clifton's wife in 2009.

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