Não informado. (1933). Population. International Union for the Scientific Investigation of Population.
Lua i Stíl Chicago (17ú heag.)Não informado. Population. London: International Union for the Scientific Investigation of Population, 1933.
Lua MLA (8ú heag.)Não informado. Population. International Union for the Scientific Investigation of Population, 1933.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.