Não informado. (1930). Extension service review. Science and Education Administration.
Lua i Stíl Chicago (17ú heag.)Não informado. Extension Service Review. Washington: Science and Education Administration, 1930.
Lua MLA (8ú heag.)Não informado. Extension Service Review. Science and Education Administration, 1930.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.