United States Government 2014, Toxic Pollutant List, Code of Federal Regulations, 40 CFR 401.15., accessed 27 March 2016.
الحكومة الفيدرالية للولايات المتحدة 2014, Toxic Pollutant List, Code of Federal Regulations, 40 CFR 401.15., accessed 27 March 2016.