*[https://www3.epa.gov/region1/npdes/stormwater/research/epa-final-report-filter-study.pdf USEPA, 2013 - Evaluation and Optimization of Bioretention Design for Nitrogen and Phosphorus Removal] | *[https://www3.epa.gov/region1/npdes/stormwater/research/epa-final-report-filter-study.pdf USEPA, 2013 - Evaluation and Optimization of Bioretention Design for Nitrogen and Phosphorus Removal] |