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Publisher: Federal Environment Agency (Umweltbundesamt) 
P.O.Box 1406 
D-06844 Dessau-Roßlau 
phone: +49-340-2103-0 
fax: +49-340-2103 2285 
Internet: http://www.umweltbundesamt.de 
Edited by: Section II 2.3 
Dagmar Larws 
Dessau-Roßlau, July 2008