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The Report On Unidentified Flying Objects by Ruppelt, Edward J.

Scientific Study Of Unidentified Flying Objects

One Small Step by David Whitehouse (2009, Hardcover)

Identified Flying Objects: A Multidisciplinary Scientific Approach to the UFO P

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The Report On Unidentified Flying Objects by Edward J. Ruppelt Ace Paperback

Aliens from Space: The Real Story of Unidentified Flying Objects Donald E Keyhoe