  The cyclotron resonance absorption spectrum in a Wigner crystal is
calculated. Effects of spin-splitting are modelled by substitutional disorder,
and calculated in the coherent potential approximation. Due to the increasing
strength of the dipole-dipole interaction, the results show a crossover from a
double-peak spectrum at small filling factors to a single-peak spectrum at
filling factors $\agt 1/6$. Radiation damping and magnetophonon scattering can
also influence the cyclotron resonance. The results are in very good agreement
with experiments.
