Polsby, Nelson W., author
Charles Scribner's Sons, 1980
Buku Teks
Asher, Herbert B., author
The Dorsey Press, 1980
Buku Teks
Asher, Herbert B., author
The Dorsey Press, 1984
Buku Teks
Neustadt, Richard E., author
John Wiley & Sons, 1961
Buku Teks
Huntington, Samuel P., author
The Belknap Press, 1981
Buku Teks