Extrinsic geometric properties of the Rozendorn surface, an isometric immersion of the Lobachevskiǐ plane in $E^5$

The lengths of the normal curvature vectors on the Rozendorn surface $F^2$ are shown to be uniformly bounded above on the whole of the surface. A regular three-dimensional submanifold $F^3$, $F^2\subset F^3 \subset E^5$, is constructed in the form of a regular leaf whose sectional curvatures in the two-dimensional directions tangent to $F^2$ are strictly negative and bounded away from zero.
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