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Inhomogeneous multidimensional cosmological models with a higher-dimensional
space-time manifold $M=M_0\times \prod_{i=1}^n M_i \ (n\geq 1)$ are investigated
under dimensional reduction to tensor-multiscalar theories. In the Einstein
conformal frame, these theories take the shape of a flat $\sigma$ model. For
the singular case where $M_0$ is two dimensional, the dimensional reduction to
dilaton gravity is preformed with different distinguished representations of
the action.
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