Cita APA (7th ed.)

PORTER MICHAEL E. (2004). COMPETITIVE ADVANTAGE. FREE PRESS.

Cita Chicago (17th ed.)

PORTER MICHAEL E. COMPETITIVE ADVANTAGE. NEW YORK: FREE PRESS, 2004.

Cita MLA (9th ed.)

PORTER MICHAEL E. COMPETITIVE ADVANTAGE. FREE PRESS, 2004.

Atenció: Aquestes cites poden no estar 100% correctes.