APA (7th ed.) Citation

Schaeffer, F. A., & Koop, C. E. (1980). Whatever happened to the human race? Marshall, Morgan & Scott.

Chicago Style (17th ed.) Citation

Schaeffer, Francis A., and Charles Everett Koop. Whatever Happened to the Human Race? London: Marshall, Morgan & Scott, 1980.

MLA (8th ed.) Citation

Schaeffer, Francis A., and Charles Everett Koop. Whatever Happened to the Human Race? Marshall, Morgan & Scott, 1980.

Warning: These citations may not always be 100% accurate.