Thomas, J. M., & Callan,Scott. (2009). Environmental economics (India ed.). Cengage Learning.
Cita Chicago (17th ed.)Thomas, Janet M., i Callan,Scott. Environmental Economics. India ed. New Dehli: Cengage Learning, 2009.
Cita MLA (8th ed.)Thomas, Janet M., i Callan,Scott. Environmental Economics. India ed. Cengage Learning, 2009.
Atenció: Aquestes cites poden no estar 100% correctes.