Não informado. (1980). Environmental Technology Letters. Science and Technology Letters.
Lua i Stíl Chicago (17ú heag.)Não informado. Environmental Technology Letters. London: Science and Technology Letters, 1980.
Lua MLA (8ú heag.)Não informado. Environmental Technology Letters. Science and Technology Letters, 1980.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.