1. Birol, F., Key World Energy Statistics, International Energy Agency (IEA). http://www.iea.org/statistics. Cited October 25, 2017.
2. China Electricity Council, Current Status of Desulphurization and Denitration of Five National Power Generating Groups in China. http://www.cec.org.cn/ yaowenkuaidi/2015-03-09/134906.html. Cited March 9, 2015.
3. Bale, V., Sustainability, 2012, vol. 4, p. 462.
4. Mohammad, S., Pak. J. Anal. Environ. Chem., 2016, vol. 17, no. 1, p. 18.
5. Gilbert, M., DSD, 2015, p. 241.