1. Abawi, G., & Widmer, T. (2000). Impact of soil health management practices on soil-borne pathogens, nematodes and root diseases of vegetable crops. Applied Soil Ecology, 15, 37–47.
2. Abbas, M., Pawoem, Z., Igba, S., Riazuddin, L. M., Ahmed, M., & Bhutto, R. (2010). Monitoring of toxic metals (Cd, Pb, As, Hg) in vegetable of Sindh, Pakistan. Kathmandu University Journal of Science, Engineering and Technology’s, 16, 60–65.
3. Abii, T. A. (2012). Levels of heavy metals (Cr, Pb, Cd) available for plants within abandoned mechanic workshops in Umuahia metropolis. Research Journal of Chemical Sciences, 2(2), 79–82.
4. Agency for Toxic Substances and Disease Registry (ATSDR). (1994). Toxicological profile for Zinc and Cobalt. US Department of Health and Human Services, Public Health Serv 205–88-0608.
5. Ajaz haja mohideena, R., Thirumalai Arasuc, V., Narayananb, K. R., & Zahir Hussaind, M. I. (2010). Bioremediation of heavy metal contaminated soil by the Exigobacterium and accumulation of Cd, Ni, Zn and Cu from soil environment. International Journal of Biology and Technology, 1(2), 94–101.