Cita APA (7th ed.)

Porter, M. E. (1998). On competition. Harvard Businesss School Publishing.

Cita Chicago (17th ed.)

Porter, Michael E. On Competition. Boston: Harvard Businesss School Publishing, 1998.

Cita MLA (9th ed.)

Porter, Michael E. On Competition. Harvard Businesss School Publishing, 1998.

Atenció: Aquestes cites poden no estar 100% correctes.