APA (7th ed.) Citation
Kay, G. F., & Apfel, E. T. (1929). The Pre-Illinoian Pleistocene-Geology of Iowa. Iowa Geolog. Survey.
Chicago Style (17th ed.) Citation
Kay, George F., and Earl T. Apfel. The Pre-Illinoian Pleistocene-Geology of Iowa. Des Moines: Iowa Geolog. Survey, 1929.
MLA (9th ed.) Citation
Kay, George F., and Earl T. Apfel. The Pre-Illinoian Pleistocene-Geology of Iowa. Iowa Geolog. Survey, 1929.
Warning: These citations may not always be 100% accurate.