APA
Radha S., The Asian Institute of Social Law and Economics S. & Sankhyan A. S. (2002). Environmental challenges of the 21st century. New Delhi: Deep and Deep Publications.
Chicago
Radha S(ED.), The Asian Institute of Social Law and Economics Shimla and Sankhyan Amar Singh(Ed.). 2002. Environmental challenges of the 21st century. New Delhi: Deep and Deep Publications.
Harvard
Radha S., The Asian Institute of Social Law and Economics S. and Sankhyan A. S. (2002). Environmental challenges of the 21st century. New Delhi: Deep and Deep Publications.
MLA
Radha S(ED.), The Asian Institute of Social Law and Economics Shimla and Sankhyan Amar Singh(Ed.). Environmental challenges of the 21st century. New Delhi: Deep and Deep Publications. 2002.