Não informado. (1932). American Forests. American Forestry Association.
Lua i Stíl Chicago (17ú heag.)Não informado. American Forests. Washington: American Forestry Association, 1932.
Lua MLA (8ú heag.)Não informado. American Forests. American Forestry Association, 1932.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.