World health Organization. (2004). Air quality guidelines,Global update 2005: Particulate matter, ozone nitrogen dioxide and sulfur dioxide. World Health Organization.
Chicago-viite (17. p.)World health Organization. Air Quality Guidelines,Global Update 2005: Particulate Matter, Ozone Nitrogen Dioxide and Sulfur Dioxide. copenhagen: World Health Organization, 2004.
MLA-viite (8. p.)World health Organization. Air Quality Guidelines,Global Update 2005: Particulate Matter, Ozone Nitrogen Dioxide and Sulfur Dioxide. World Health Organization, 2004.
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