Savage, Donald T.
John Wiley & Sons, 1977
Buku Teks
Einzig, Paul
Macmillan, 1965
Buku Teks
by International Monetary Fund
International Monetary Fund, 1999
Buku Teks
by International Monetary Fund
International Monetary Fund, 1985
Buku Teks
editor, Brian J. Terry
Toppan Company, 1997
Buku Referensi