1. Analytical Data, Sample Locations, and Descriptive Information, Analytical Methods and Sampling Techniques, Database Perspective, and Bibliographic References for Selected U.S. Coal Samples: U.S Geological Survey Open-file Report 97–134;Bragg,1997
2. Mercury concentration in coal—unraveling the puzzle;Toole-O'Neil;Fuel,1999
3. US EPA. https.//www.epa.gov/mats/cleaner-power-plants#controls (Accessed 7 September 2016).
4. National Emission Standards for Hazardous Air Pollutants From Coal- and Oil-Fired Electric Utility Steam Generating Units and Standards of Performance for Fossil-Fuel-Fired Electric Utility, Industrial-Commercial-Institutional, and Small Industrial-Commercial-Institutional Steam Generating Units. 40 CFR Parts 60 and 63. Federal Register 77:32 (Feb 16, 2012) p. 24976.
5. Federal Implementation Plans To Reduce Interstate Transport of Fine Particulate Matter and Ozone. 40 CFR Parts 51, 52, 72, 78, and 97. Federal Register 76 FR 48208, August 8, 2011.