1. Ahmad, M. S., & Ashraf, M. (2011). Essential roles and hazardous effects of nickel in plants. Reviews of Environmental Contamination and Toxicology, 214, 125–167.
2. Alam, M. G. M., Snow, E. T., & Tanaka, A. (2003). Arsenic and heavy metal contamination of vegetables grown in Santa village, Bangladesh. Science of the Total Environment, 308, 83–96.
3. APHA. (1992). Standard methods for examination of water and wastewater. Washington DC: American Public Health Association.
4. ATSDR (1999a). Toxicological profile for cadmium and nickel. Agency for toxic substances and disease registry, US department of health and human services, public health service. 205-93-0606.
5. ATSDR (1999b). Toxicological Profile for Lead. Agency for Toxic Substances and Disease Registry, US Department of Health and Human Services, Public Health Service. 205-93-0606.