Cita APA (7th ed.)
Heinrichs, W. H. (1989). Threshold of war: Franklin D. Roosevelt and American entry into World War II. Oxford University Press.
Cita Chicago (17th ed.)
Heinrichs, Waldo H. Threshold of War: Franklin D. Roosevelt and American Entry into World War II. New York: Oxford University Press, 1989.
Cita MLA (9th ed.)
Heinrichs, Waldo H. Threshold of War: Franklin D. Roosevelt and American Entry into World War II. Oxford University Press, 1989.
Atenció: Aquestes cites poden no estar 100% correctes.