A classification of 3-type curves in Minkowski 3-space . I.
A classification of 3-type curves in Minkowski 3-space e_1^3, II
A common characterization of the curvature axis for ruled surfaces and curves. (Eine gemeinsame Kennzeichnung der Krümmungsachse bei Regelflächen und Kurven.)
A conjecture on minimal surfaces
Simple computations support the conjecture that a small spherical surface with its center on a minimal surface cannot be divided by the minimal surface into two portions with different area.
A contribution to the Cartan's method of specialization of frames
A contribution to the connection of V. Hlavatý
A criterion for pure unrectifiability of sets (via universal vector bundle)
Let m,n be positive integers such that m < n and let G(n,m) be the Grassmann manifold of all m-dimensional subspaces of ℝⁿ. For V ∈ G(n,m) let denote the orthogonal projection from ℝⁿ onto V. The following characterization of purely unrectifiable sets holds. Let A be an -measurable subset of ℝⁿ with . Then A is purely m-unrectifiable if and only if there exists a null subset Z of the universal bundle such that, for all P ∈ A, one has . One can replace “for all P ∈ A” by “for -a.e. P ∈...
A description of derivations of the algebra of symmetric tensors
In this paper the symmetric differential and symmetric Lie derivative are introduced. Using these tools derivations of the algebra of symmetric tensors are classified. We also define a Frölicher-Nijenhuis bracket for vector valued symmetric tensors.
A Dirichlet problem for an H-system with variable H.
A finiteness result in the free boundary value problem for minimal surfaces
A four-vertex theorem for space curves.
A functional expression for the curvature of hyper-dimensional Riemannian spaces.
A Gauss-like map associated to a surface in IR3.
A generalization of a theorem of S. Gołąb and M. Kucharzewski
A generalization of Frenet's frame for non-degenerate quadratic forms with any index
A generalization of Nehari's univalence criterion.
A generalization of Steiner Symmetrization for immersed surfaces and its applications.
A generalization of the Holditch theorem for the planar homothetic motions
In this paper, under the one-parameter closed planar homothetic motion, a generalization of Holditch Theorem is obtained by using two different line segments (with fixed lengths) whose endpoints move along two different closed curves.
A generalization of the Schwarzian via Clifford numbers.
A geometric characterization of helicoidal surfaces of constant mean curvature.