Cita APA (7th ed.)
Hart, G. (2004). The fourth power: A grand strategy for the United States in the twenty-first century. Oxford University Press.
Cita Chicago (17th ed.)
Hart, Gary. The Fourth Power: A Grand Strategy for the United States in the Twenty-first Century. New York: Oxford University Press, 2004.
Cita MLA (9th ed.)
Hart, Gary. The Fourth Power: A Grand Strategy for the United States in the Twenty-first Century. Oxford University Press, 2004.
Atenció: Aquestes cites poden no estar 100% correctes.