Haney, Lewis H., author
Macmillan, 1949
Buku Teks
Kotler, Philip, author
The Free Press , 1997
Buku Teks
United Nations
The Stanley Foundation, 1985
Buku Teks
Wight, Jonathan B.
Prentice-Hall, 2002
Buku Teks
Thurow, Lester C., author
HarperCollins, 1999
Buku Teks