Cunningham, W. P. (2007). Environmental science A global concern Wlliam P. Cunningham. McGraw-Hill.
Lua i Stíl Chicago (17ú heag.)Cunningham, William P. Environmental Science A Global Concern Wlliam P. Cunningham. McGraw-Hill, 2007.
Lua MLA (8ú heag.)Cunningham, William P. Environmental Science A Global Concern Wlliam P. Cunningham. McGraw-Hill, 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.