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Lua i Stíl Chicago (17ú heag.)United Nations Population Fund. The State of World Population 1999: 6billion : A Time for Choices. New York: UNFPA, 1999.
Lua MLA (8ú heag.)United Nations Population Fund. The State of World Population 1999: 6billion : A Time for Choices. UNFPA, 1999.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.