Banfield, Edward C., author
Random House, 1967
Buku Teks
Christian Soe
McGraw-Hill, 2004
Buku Teks
Barringron, Lowell, author
Wadsworth and Cengage Learning, 2013
Buku Teks
editors, Robert E. Ward and Roy C. Macridis
Prentice-Hall, 1963
Buku Teks
edited by Roy C. Macridis, Bernard E. Brown
Dorsey Press, 1968
Buku Teks