APA (7th ed.) Citation

Leet, L. D., & Leet, F. J. (1961). The world of geology. McGraw-Hill.

Chicago Style (17th ed.) Citation

Leet, L. Don, and Florence J. Leet. The World of Geology. New York: McGraw-Hill, 1961.

MLA (9th ed.) Citation

Leet, L. Don, and Florence J. Leet. The World of Geology. McGraw-Hill, 1961.