0-tight surfaces with boundary and the total curvature of curves in surfaces
3D-Darboux motions in 4-dimensional Euclidean space.
3rd order differential invariants of coframes
3-type curves in the Euclidean space .
3-type curves in the Euclidean space E5
3-type Curves on Hyperboloids of Revolution and Cones of Revolution
4-Dimensional (Para)-Kähler-Weyl Structures
A boundary value problem in the hyperbolic space.
A bridge principle for minimal and constant mean curvature submanifolds of RN.
A characterization for isometries and conformal mappings of pseudo-Riemannian manifolds.
A characterization of a minimal submanifold in
A characterization of Chen surfaces in .
A characterization of collineations by order geometry.
A characterization of hyperspheres in the quaternionic space
A characterization of n-dimensional hypersurfaces in with commuting curvature operators
Let Mⁿ be a hypersurface in . We prove that two classical Jacobi curvature operators and commute on Mⁿ, n > 2, for all orthonormal pairs (x,y) and for all points p ∈ M if and only if Mⁿ is a space of constant sectional curvature. Also we consider all hypersurfaces with n ≥ 4 satisfying the commutation relation , where , for all orthonormal tangent vectors x,y,z,w and for all points p ∈ M.
A characterization of osculating maps
A characterization of regular saddle surfaces in the hyperbolic and spherical three-space.
A class of boundary problems for extremal surfaces of mixed type in Minkowski 3-space.
A class of projectively flat surfaces.
A classfication of 3-type curves in Minkowski 3-space . II.