Não informado. (1949). Abstracts of recent published material on soil and water conservation. Agricultural Research Service, Soil and Water Conservation Division.
Lua i Stíl Chicago (17ú heag.)Não informado. Abstracts of Recent Published Material on Soil and Water Conservation. Washington: Agricultural Research Service, Soil and Water Conservation Division, 1949.
Lua MLA (8ú heag.)Não informado. Abstracts of Recent Published Material on Soil and Water Conservation. Agricultural Research Service, Soil and Water Conservation Division, 1949.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.