APA (7e ed.) Bronvermelding

Husain, M. (2018). Environment and ecology- 4th ed For Civil Service Exam (4th.). CL Media(P) Ltd.

Chicago (17e ed.) Bronvermelding

Husain, Majid. Environment and Ecology- 4th Ed For Civil Service Exam. 4th. New Delhi: CL Media(P) Ltd, 2018.

MLA (9e ed.) Bronvermelding

Husain, Majid. Environment and Ecology- 4th Ed For Civil Service Exam. 4th. CL Media(P) Ltd, 2018.