[[VIII-1]] Keyhoe, D. E. The Flying Saucer Conspiracy. New York: Henry Holt & Co., 1955.
[[VIII-2]] Air Force Files.
[[VIII-3]] Ruppelt, E. J. The Report on Unidentified Flying Objects. Garden City, N.Y.: Doubleday & Co., 1956.
[[VIII-4]] Plank, V. G. “Spurious Echoes on Radar, A Survey.” Astia Document No. AD-215470, AFCRC-TR-59-210 (May 1959).
[[VIII-5]] Borden, R. C., and Vickers, T. K. “A Preliminary Study of Unidentified Targets Observed on Air Traffic Control Radars.” Technical Development Report No. 180, Civil Aeronautics Administration, Technical Development and Evaluation Center, Indianapolis, Indiana (May 1953).
[[VIII-6]] “Radar Objects Over Washington,” Air Weather Service Bulletin (September 1954), pp. 52–57.
[[VIII-7]] Menzel, D. H. Elementary Manual of Radio Propagation. Englewood Cliffs, N.J.: Prentice-Hall, Inc., 1948.
[[VIII-7a]] —— “Why Flying Saucers Show Up on Radar.” Look magazine (September 9, 1952).
[[VIII-8]] Keyhoe, D. E. “What Radar Tells about Flying Saucers.” True magazine (December 1952), p. 25 ff.
[[VIII-9]] Plank, V. G. Personal communication.