Thomas, J. M., & Callan,Scott. (2009). Environmental economics (India ed.). Cengage Learning.
Lua i Stíl Chicago (17ú heag.)Thomas, Janet M., agus Callan,Scott. Environmental Economics. India ed. New Dehli: Cengage Learning, 2009.
Lua MLA (8ú heag.)Thomas, Janet M., agus Callan,Scott. Environmental Economics. India ed. Cengage Learning, 2009.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.