Não informado. (2019). Statistical Yearbook. United Nations, Department of International Economic.
Lua i Stíl Chicago (17ú heag.)Não informado. Statistical Yearbook. New York: United Nations, Department of International Economic, 2019.
Lua MLA (8ú heag.)Não informado. Statistical Yearbook. United Nations, Department of International Economic, 2019.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.