APA (7th ed.) Citation

Porter, M. E. (1985). Competitive advantage: Creating and sustaining superior performance. Free Press [etc.].

Chicago Style (17th ed.) Citation

Porter, Michael E. Competitive Advantage: Creating and Sustaining Superior Performance. New York [etc.]: Free Press [etc.], 1985.

MLA (9th ed.) Citation

Porter, Michael E. Competitive Advantage: Creating and Sustaining Superior Performance. Free Press [etc.], 1985.