Joseph, K. (2004). Essentials of environmental studies. Pearson Education.
Lua i Stíl Chicago (17ú heag.)Joseph, Kurian. Essentials of Environmental Studies. Delhi: Pearson Education, 2004.
Lua MLA (9ú heag.)Joseph, Kurian. Essentials of Environmental Studies. Pearson Education, 2004.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.