%0 Book %D 2002 %T Growth of Norway spruce (Picea abies) in relation to the AOT40 index. %A Skarby, L. %A Ottoson, S. %A Karlsson, P.E. %A Wallin, G. %A Sellden, G. %A Medin, E. %A Pleijel, H. %9 Background paper presented at the UNECE Workshop Establishing Ozone Critical Levels II, Goteborg November 2002