Geophysical Variables and Behavior: XXXIV. Further Comments

Persinger M. A. Earthquake activity and antecedent UFO report numbers. Perceptual and Motor Skills, 1980, 50, 791–797.

Persinger M. A. Derr J. S. Geophysical variables and behavior: XXXII. Evaluations of UFO reports in an area of infrequent seismicity: The Carman, Manitoba, episode. Perceptual and Motor Skills, 1985, 61, 807–813.

Rutkowski C. A. The UFOROM data file—manufocat. Winnipeg, Manitoba: Private publication, 1983.

Sheaffer R. The UFO verdict: Examining the evidence. Buffalo, NY: Prometheus Books, 1981.