Cita APA (7th ed.)

Verma, P. S., & Agarwal, V. K. (2000). Environmental biology (Principles of ecology). S. Chand & Company.

Cita Chicago (17th ed.)

Verma, P. S., i V. K. Agarwal. Environmental Biology (Principles of Ecology). New Delhi: S. Chand & Company, 2000.

Cita MLA (9th ed.)

Verma, P. S., i V. K. Agarwal. Environmental Biology (Principles of Ecology). S. Chand & Company, 2000.