Book was the official USAF project to investigate UFOs. The USAF UFO
program was active from January 1948 until December 1969, and investigated
approximately 13,000 UFO reports. Following the closure, the project files were
transferred to the Air
Force Archives at Maxwell AFB, Montgomery, AL, and later, to the National
Archives for redaction and public release in 1976. The files currently reside
at the National Archives in College Park, Maryland. See: http://www.archives.gov/research/guide-fed-records/groups/341.html#341.15.
The index for the 94 rolls of 35mm microfilm (T1206) of the Project Blue Book files is available from: http://www.minotb52ufo.com/pdf/T1206-PBB-Microfilm-index.pdf.