Cita APA (7th ed.)

Roosevelt, T., Hay, J., Trevelyan, S. G. O., & Gray, D. (1954). Cowboys and kings: Three great letters. Harvard University Press.

Cita Chicago (17th ed.)

Roosevelt, Theodore, John Hay, Sir George Otto Trevelyan, i David Gray. Cowboys and Kings: Three Great Letters. Cambridge: Harvard University Press, 1954.

Cita MLA (9th ed.)

Roosevelt, Theodore, et al. Cowboys and Kings: Three Great Letters. Harvard University Press, 1954.