Cita APA (7th ed.)
1987 Statistical Yearbook Annuaire statistique. United Nations.
Cita Chicago (17th ed.)
1987 Statistical Yearbook Annuaire Statistique. New York: United Nations.
Cita MLA (9th ed.)
1987 Statistical Yearbook Annuaire Statistique. United Nations.
Atenció: Aquestes cites poden no estar 100% correctes.