Sengar, R., & Kumar, A. (2017). Environment science question bank: A handbook for competitive examinations. CBS Publishers.
Chicago Stili AlıntıSengar, R.S, ve Amit Kumar. Environment Science Question Bank: A Handbook for Competitive Examinations. New Delhi: CBS Publishers, 2017.
MLA AlıntıSengar, R.S, ve Amit Kumar. Environment Science Question Bank: A Handbook for Competitive Examinations. CBS Publishers, 2017.
Uyarı: Bu alıntı herzaman %100 doğru olmayabilir..