On the power structure over the Grothendieck ring of varieties and its   applications
  We discuss the notion of a power structure over a ring and the geometric description of the power structure over the Grothendieck ring of complex quasi-projective varieties and show some examples of applications to generating series of classes of configuration spaces (for example, nested Hilbert schemes of J. Cheah) and wreath product orbifolds. 
S.M. Gusein-Zade, I. Luengo and A. Melle-Hernandez