R. C. JAGGI and R. K. SHARMA, “Evaluation of extractants for available sulphur in soils of Kangra Valley”, Indian J Agri Sci, vol. 69, no. 6, Jan. 2013, Accessed: Jun. 14, 2026. [Online]. Available: https://epubs.icar.org.in/index.php/IJAgS/article/view/26827