http://www.who.int/quantifying_ehimpacts/publications/en/ebd9.pdf
http://www.who.int/ceh/capacity/noise.pdf
http://www.who.int/occupational_health/publications/noise1.pdf
http://www.who.int/occupational_health/publications/noise2.pdf
http://www.who.int/occupational_health/publications/noise3.pdf
http://www.who.int/occupational_health/publications/noise4.pdf
http://www.who.int/occupational_health/publications/noise5.pdf
http://www.who.int/occupational_health/publications/noise6.pdf
http://www.who.int/occupational_health/publications/noise7.pdf
http://www.who.int/occupational_health/publications/noise8.pdf
http://www.who.int/occupational_health/publications/noise9.pdf
http://www.who.int/occupational_health/publications/noise10.pdf
http://www.who.int/occupational_health/publications/noise11.pdf
http://www.who.int/occupational_health/publications/noise12.pdf