  Stimulated by the idea of PRISM, a very high intensity muon ring with rather
low energy, we consider possibilities of observing CP-violation effects in
neutrino oscillation experiments. More than 10% of CP-violation effect can be
seen within the experimentally allowed region. Destructive sum of matter effect
and CP-violation effect can be avoided with use of initial nu_e beam. We
finally show that the experiment with (a few) x 100 MeV of neutrino energy and
(a few) x 100 km of baseline length, which is considered in this paper, is
particularly suitable for a search of CP violation in view of statistical
error.
