16-dimensional compact projective planes with 3 fixed points.
A family of flat Minkowski planes admitting 3-dimensional simple groups of automorphisms.
Folding on the wedge sum of graphs and their fundamental group.
Generating Closed 2-Cell Embeddings in the Torus and the Projective Plane.
Local rigidity of aspherical three-manifolds
In this paper we construct, for each aspherical oriented -manifold , a -dimensional class in the -homology of whose norm combined with the Gromov simplicial volume of gives a characterization of those nonzero degree maps from to which are homotopic to a covering map. As an application we characterize those degree one maps which are homotopic to a homeomorphism in term of isometries between the bounded cohomology groups of and .
Manifolds of nonpositive curvature and their buildings
Noncompact, almost simple groups operating on locally compact, connected translation planes.
On a special class of Frobenius groups admitting planar partitions.
On topological Tits buildings and their classification
Partitionen Liescher und algebraischer Gruppen.
Remarks on projectivities.
Shells of monotone curves
We determine in the form of curves corresponding to strictly monotone functions as well as the components of affine connections for which any image of under a compact-free group of affinities containing the translation group is a geodesic with respect to . Special attention is paid to the case that contains many dilatations or that is a curve in . If is a curve in and is the translation group then we calculate not only the components of the curvature and the Weyl tensor but...
Spherical Complexes and Nonprojective Tone Varieties.
Stable Planes with Isotropic Points.
The Nonexistence of Certain Topological Polygons.
The Skew-Hyperbolic Motion Group of the Quaternion Plane.
Ueber die Thatsachen, die der Geometrie zum Grunde liegen.
Двумерные кинематики ограниченной кривизны. I.
Двумерные кинематики ограниченной кривизны. II.
Дискретные группы без кручения в , порожденные сдвигами