Tham khảo Dự_án_Condign

  1. 1 2 3 4 5 6 7 Simpson, Mark (2006-05-07) "UFO study finds no sign of aliens", BBC News
  2. 1 2 3 Randerson, James (2006-09-25) Is there anybody out there? How the men from the ministry hid the hunt for UFOs, The Guardian (2007-12-02)
  3. ↑ http://www.nickpope.net/project-condign.htm
  4. 1 2 3 4 "Unidentified Aerial Phenomena in the UK Air Defence Region", Defence Intelligence Staff (2000)
  5. ↑ "Unidentified Aerial Phenomena in the UK Air Defence Region: Executive Summary", Defence Intelligence Staff (2000), Pages 7-8
  6. ↑ "Unidentified Aerial Phenomena in the UK Air Defence Region: Executive Summary", Defence Intelligence Staff (2000), Pages 11,12,
  7. ↑ "Unidentified Aerial Phenomena in the UK Air Defence Region: Executive Summary", Defence Intelligence Staff (2000), Pages 9-10