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Evens, Anne et al. "The Impact of Low-Level Lead Toxicity on School Performance among Children in the Chicago Public Schools: A Population-Based Retrospective Cohort Study." Environmental Health 14 (2015): 21. PMC. Web. 28 Jan. 2016.
Evens, A., Hryhorczuk, D., Lanphear, B. P., Rankin, K. M., Lewis, D. A., Forst, L., & Rosenberg, D. (2015). The impact of low-level lead toxicity on school performance among children in the Chicago Public Schools: a population-based retrospective cohort study. Environmental Health, 14, 21. https://doi.org/10.1186/s12940-015-0008-9