Odiba, P. A., T. E. Odumakara, I. D. Shehu, and I. Haruna. “The Concentration of Lead in Some Herbs Sold in Port-Harcourt Nigeria”. The International Journal of Science & Technoledge, vol. 3, no. 6, June 2015, http://internationaljournalcorner.com/index.php/theijst/article/view/124490.