9Srivastava RK, Hall RE, Khan S, et al. Nitrogen oxides emission control options for coal-fired electric utility boilers[J]. J. Air & Waste Manage. Assoc., 2005, 55(9): 1367-1388.
10Slawomir Poskrobko, Danuta Krol, Jan Lach. A primary method for reducing nitrogen oxides in coal combustion through addition of Bio-CONOx[J]. Fuel Processing Technology, 2012 (12) : 58-63.