Footnote 7. Nduka, J.K., and O. E. Orisakwe, Assessment of environmental distribution of lead in some municipalities of South-Eastern Nigeria, Int. J. Environ. Res., Public Health, 7 (2010), 2501-2513; doi:10.3390/ijerph7062501, http://pubmedcentralcanada.ca/pmcc/articles/PMC2905563/pdf/ijerph-07-02501.pdf

Additional Resources

5.  Environment and Climate Change Canada, http://www.ec.gc.ca/Air/