  Measurements of the structure function xF3(gamma-Z) are now becoming
available in charged lepton deep inelastic scattering at HERA. The correction
factors which are necessary to compare these with measurements of xF3(nu N) in
neutrino-nucleon scattering are deduced and a comparison is made between the H1
and the CCFR data. A sum rule is derived for the structure function
xF3(gamma-Z)measured in charged lepton scattering which is the analogue of the
Gross Llewellyn-Smith sum rule for neutrino-nucleon scattering.
