APA (7th ed.) Citation

Ruffin, R., & Gregory, P. R. (1993). Principles of microeconomics (5th ed.). HarperCollins College Publishers.

Chicago Style (17th ed.) Citation

Ruffin, Roy, and Paul R. Gregory. Principles of Microeconomics. 5th ed. New York, NY: HarperCollins College Publishers, 1993.

MLA (9th ed.) Citation

Ruffin, Roy, and Paul R. Gregory. Principles of Microeconomics. 5th ed. HarperCollins College Publishers, 1993.