Não informado. (1981). Balance of Payments Statistics Yearbook. International Monetary Fund.
Chicago-Zitierstil (17. Ausg.)Não informado. Balance of Payments Statistics Yearbook. Washington: International Monetary Fund, 1981.
MLA-Zitierstil (8. Ausg.)Não informado. Balance of Payments Statistics Yearbook. International Monetary Fund, 1981.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.