"United States Air Force Efforts to Investigate UFOs: Great Plains Encounters"https://www.sdshspress.com/journal/south-dakota-history-12-1/united-states-air-force-efforts-to-investigate-ufos-great-plains-encountershttps://www.sdshspress.com/@@site-logo/sdshp-logo.jpg
"United States Air Force Efforts to Investigate UFOs: Great Plains Encounters"