Abu, Mary L., et al. “Evaluation of Soil Amended With Graded Levels of Craseonycteris Thonglongyai Dung on the Improvement of Mineral Element Constituents in the Leaf of Cnidoscolus Aconitifolius (Tree Spinach): doi.org 10.26538 Tjnpr V4i11.29”. Tropical Journal of Natural Product Research (TJNPR), vol. 4, no. 11, Nov. 2020, pp. 1015-8, https://www.tjnpr.org/index.php/home/article/view/974.