Cita APA (7th ed.)

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

Cita Chicago (17th ed.)

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

Cita MLA (9th ed.)

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