Oxford University Press, 1964
Buku Teks
New York University Press, 1979
Buku Teks
Kennan, George F., 1904-, author
Princeton University Press , 1954
Buku Teks
McCormick, James M., author
Thomson, 2005
Buku Teks
Herrick, Christopher, author
Longman, 2003
Buku Teks