Howell, W. G., & Brent, D. M. (2013). Thinking about the presidency: The primacy of power. Princeton University Press.
Chicago-viite (17. p.)Howell, William G., ja David Milton Brent. Thinking About the Presidency: The Primacy of Power. Princeton: Princeton University Press, 2013.
MLA-viite (9. p.)Howell, William G., ja David Milton Brent. Thinking About the Presidency: The Primacy of Power. Princeton University Press, 2013.
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