Não informado. (1973). Energy index. Environment Information Center, Energy Reference Department.
Lua i Stíl Chicago (17ú heag.)Não informado. Energy Index. New York: Environment Information Center, Energy Reference Department, 1973.
Lua MLA (8ú heag.)Não informado. Energy Index. Environment Information Center, Energy Reference Department, 1973.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.