Não informado. World population year bulletin. World Federation of United Nations Associations.
Lua i Stíl Chicago (17ú heag.)Não informado. World Population Year Bulletin. Geneva, Suíça: World Federation of United Nations Associations.
Lua MLA (8ú heag.)Não informado. World Population Year Bulletin. World Federation of United Nations Associations.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.