K.C. Patel and A.K. Shukla, Dileep Kumar*, V.P. Ramani,. 2021. “Establishing Critical Limits for Nickel in Soil and Plant for Predicting the Response of Spinach (Spinacia Oleracea)”. Journal of the Indian Society of Soil Science 69 (1). https://epubs.icar.org.in/index.php/JISSS/article/view/113091.