Balaam, David N., 1950-
Pearson/Prentice Hall, 2005
Buku Teks
Kaplan, Morton A.
John Wiley & Sons, 1961
Buku Teks
Bhagwati, Jagdish
MIT Press, c1991
Buku Teks
Balaam, David N., 1950-
Prentice-Hall, 1996
Buku Teks
edited by W. Ladd Hollist
Westview Press, 1985
Buku Teks