M. K. SINGH, S. K. PAL, R. THAKUR, and U. N. VERMA, “Energy input-output relationship of cropping systems”, Indian J Agri Sci, vol. 67, no. 6, May 2013, Accessed: Oct. 28, 2025. [Online]. Available: https://epubs.icar.org.in/index.php/IJAgS/article/view/29914