Ghani, Abdul, Ameen Ullah Shah, and Umer Akhtar. 2010. “Effect of Lead Toxicity on Growth, Chlorophyll and Lead (Pb+) Contents of Two Varieties of Maize (Zea Mays L.)”. Pakistan Journal of Nutrition 9 (9): 887–891. https://doi.org/10.3923/pjn.2010.887.891.