  We show the possible existence of the Wigner crystal (WC) in the Fractional
Quantum Hall (FQH) regime. We find that the Landau-level mixing (LLM) will
lower the energy of the WC significantly in the high-density regime. The WC is
lower in energy than the FQH liquid in the high-density regime. We conclude
that the crystal phase is expected at high density for rotating dipolar gases,
which is consistent with non-rotating dipolar gases, but is inconsistent with
the low-density conclusion from Baranov et al. [Phys. Rev. Lett. 100, 200402
(2008)], where the effect of LLM is ignored.
