APA (7th ed.) Citation

Amacher, R. C., & Ulbrich, H. H. (1989). Principles of economics (Fourth edition.). South-Western.

Chicago Style (17th ed.) Citation

Amacher, Ryan C., and Holley H. Ulbrich. Principles of Economics. Fourth edition. Cincinnati, Ohio: South-Western, 1989.

MLA (9th ed.) Citation

Amacher, Ryan C., and Holley H. Ulbrich. Principles of Economics. Fourth edition. South-Western, 1989.