Comparison of NNLO and all-orders estimates of corrections to the GLS   and Bjorken sum rules
  For the GLS and Bjorken DIS sum rules we compare fixed-order NNLO perturbative QCD estimates, and all-orders resummed estimates, with the available data, in order to assess the reliability of fixed-order perturbation theory at rather small Q^2 values. Fits are also performed for non-perturbative power corrections using a recently proposed model. 
Paul M. Brooks and C.J. Maxwell