Cita APA (7th ed.)

Bhatnagar Aditya. (2010). Principles of environmental studies. Oxford University Press.

Cita Chicago (17th ed.)

Bhatnagar Aditya. Principles of Environmental Studies. Delhi: Oxford University Press, 2010.

Cita MLA (9th ed.)

Bhatnagar Aditya. Principles of Environmental Studies. Oxford University Press, 2010.