Não informado. Environmental Pollution and Control. U.S. Department of Commerce, National Technical Information Service.
Lua i Stíl Chicago (17ú heag.)Não informado. Environmental Pollution and Control. Springfield, Va: U.S. Department of Commerce, National Technical Information Service.
Lua MLA (8ú heag.)Não informado. Environmental Pollution and Control. U.S. Department of Commerce, National Technical Information Service.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.