Siemers, D. J. (2009). Presidents and political thought. University of Missouri Press.
芝加哥风格引文Siemers, David J. Presidents and Political Thought. Columbia: University of Missouri Press, 2009.
MLA引文Siemers, David J. Presidents and Political Thought. University of Missouri Press, 2009.
警告：这些引文格式不一定是100％准确.