NARENDER, R. S. MALIK, and R. P. NARWAL, “Critical limit of copper in soil and plant for predicting response of oat (Avena sativa) in soils of Haryana”, Indian J Agri Sci, vol. 84, no. 3, pp. 382–4, Mar. 2014, doi: 10.56093/ijas.v84i3.38588.