John Ferejohn, Jack N. Rakove, Jonathan Riley
Cambridge University Press, 2001
Buku Teks
Fisher, Louis, author
McGraw-Hill, 1988
Buku Teks
Swisher, Carl Brent, author
Houghton Miffiln, 1943
Buku Teks
McLaughlin, Andrew C., author
Appleton Century Crofts, 1935
Buku Teks
Taylor, Telford
Ohio State University Press, 1969
Buku Teks