APA (7th ed.) Citation

Keyhoe, D. E. (1953). Flying saucers from outer space. Henry Holt.

Chicago Style (17th ed.) Citation

Keyhoe, Donald E. Flying Saucers from Outer Space. New York: Henry Holt, 1953.

MLA (9th ed.) Citation

Keyhoe, Donald E. Flying Saucers from Outer Space. Henry Holt, 1953.