00253nam a2200121Ia 4500008004100000082001200041100001300053245002700066260001200093260000900105260000900114300000800123160427s9999    xx            000 0 und d  a658 KOC  aKoch, R. 4aThe 80 _ 20 Principle   aLondon   bN.B.  c2010  a293