Cita APA (7th ed.)

Porter, M. E. (1990). The competitive advantage of nations. Free Press.

Cita Chicago (17th ed.)

Porter, Michael E. The Competitive Advantage of Nations. New York: Free Press, 1990.

Cita MLA (9th ed.)

Porter, Michael E. The Competitive Advantage of Nations. Free Press, 1990.

Atenció: Aquestes cites poden no estar 100% correctes.