The consistent reduction of the differential calculus on the quantum
group $GL_{q}(2,C)$ to the differential calculi on its subgroups and
$σ$-models on the quantum group manifolds $SL_{q}(2,R)$,
$SL_{q}(2,R)/U_{h}(1)$, $C{q}(2|0)$ and infinitesimal t