U.S. Government UFO Web Page:
“Frequently Asked Questions:
Unidentified Flying Objects Research Guide”,
21 January 2010 (Naval History & Heritage Command,
United States Department of the Navy,
Washington, D.C.)

On this web page, the U.S. Navy presents a bibliography of original U.S. government documents and selected published sources:

http://www.history.navy.mil/faqs/faq29-1.htm

Seal of the U.S. Department of the Navy
(wikimedia.org image)