By using the sets of crystal field parameters recently deduced by Allenspach et al. for ErBa2Cu3O
x (6 < x < 7) from inelastic neutron scattering experiments, the crystal field contribution of the Er ion to the
low-temperature specific heat has been calculated at zero field and at a field of 5 T applied parallel and
perpendicular to the c axis. The calculated results are compared with available specific-heat data for a
sintered polycrystalline sample and found to be in close agreement with the experimental results. ?? 1992.
