  We provide, for each natural number $n$ and each class among
$D_n(\Sigma^0_1)$, $\bar D_n(\Sigma^0_1)$ and $D_{2n+1}(\Sigma^0_1)\oplus\bar
D_{2n+1}(\Sigma^0_1)$, a regular language whose associated omega-power is
complete for this class.
