Perturbative description of inclusive single hadron production at HERA
  Light charged hadron production data in the current fragmentation region at HERA are calculated using next-to-leading order perturbative calculations and fragmentation functions obtained from similar data from e+ e- reactions. General good agreement is found at large photon virtuality Q^2 and intermediate momentum fraction x_p, consistent with fragmentation function universality. The description of the small x_p and Q^2 region is improved by incorporating hadron mass effects. 
Simon Albino