APA (7th ed.) Citation

Sanderson, I. T. (1967). Uninvited visitors: A biologist looks at UFO's. A Cowles Book.

Chicago Style (17th ed.) Citation

Sanderson, Ivan T. Uninvited Visitors: A Biologist Looks at UFO's. New York: A Cowles Book, 1967.

MLA (8th ed.) Citation

Sanderson, Ivan T. Uninvited Visitors: A Biologist Looks at UFO's. A Cowles Book, 1967.