  A rotational model is developed from a new version of the two-parameter
quantum algebra $U_{qp}({\rm u}_2)$. This model is applied to the description
of some recent experimental data for the rotating superdeformed nuclei
$^{192-194-196-198}{\rm Pb}$ and $^{192-194 }{\rm Hg}$. A comparison between
the $U_{qp}({\rm u}_2)$ model presented here and the Raychev-Roussev-Smirnov
model with $U_{q }({\rm su}_2)$ symmetry shows the relevance of the
introduction of a second parameter of a ``quantum algebra'' type.
