Delvin, S. (2007). environmental problems and issues. Sarup.
Lua i Stíl Chicago (17ú heag.)Delvin, Samuel. Environmental Problems and Issues. New Delhi: Sarup, 2007.
Lua MLA (9ú heag.)Delvin, Samuel. Environmental Problems and Issues. Sarup, 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.