http://www.environment.nsw.gov.au/soe/soe2009/chapter4/chp_4.1.htm#4.1.4
http://www.environment.gov.au/atmosphere/airquality/index.html
http://www.bp.com/sectiongenericarticle.do?categoryId=9032772&contentId=7059988
http://www.mja.com.au/public/issues/177_11_021202/kje10481_fm.html#CACHJIJJ
http://www.environment.nsw.gov.au/soe/soe2003/chapter3/chp_3.3.htm#3.3.18
http://www.environment.nsw.gov.au/airwatch/perceptions.htm
http://www.esa.int/esaEO/SEM340NKPZD_index_0.html
http://www.cleartheair.nsw.gov.au/science_and_research/impact.aspx
http://www.environment.gov.au/soe/2001/publications/theme-reports/atmosphere/atmosphere04-4a.html