  The eta-gamma and eta'-gamma transition form factors are analyzed to
leading-twist accuracy and next-to-leading order (NLO) of perturbative QCD.
Using an eta-eta' mixing scheme and all currently available experimental data
the lowest Gegenbauer coefficients of the distribution amplitudes for the
valence octet and singlet quark-antiquark and the gluon-gluon Fock components
are extracted. Predictions for the g*g*eta' vertex function are presented. We
also comment on the new BELLE results for the pi-gamma transition form factor.
