Sengar, R., & Kumar, A. (2017). Environment science question bank: A handbook for competitive examinations. CBS Publishers.
Stile di citazione ChicagoSengar, R.S, e Amit Kumar. Environment Science Question Bank: A Handbook for Competitive Examinations. New Delhi: CBS Publishers, 2017.
Citazione MLASengar, R.S, e Amit Kumar. Environment Science Question Bank: A Handbook for Competitive Examinations. CBS Publishers, 2017.
Attenzione: Queste citazioni potrebbero non essere precise al 100%.