On hyperplanes and free subspaces of affine Klingenberg spaces. (Summary).
On perspectivities in incidence geometries of grade n
On Rusakov’s -ary -groups
Properties of -ary groups connected with the affine geometry are considered. Some conditions for an -ary -group to be derived from a binary group are given. Necessary and sufficient conditions for an -ary group -derived from an additive group of a field to be an -group are obtained. The existence of non-commutative -ary -groups which are not derived from any group of arity for every , is proved.
On the interpoint distance sum inequality.
One generalization of planar partitions of Abelian groups
Recursive constructions for skew resolutions in affine geometries.
Reflection loops of spaces with congruence and hyperbolic incidence structure
In an absolute space with congruence there are line reflections and point reflections. With the help of point reflections one can define in a natural way an addition + of points which is only associative if the product of three point reflection is a point reflection again. In general, for example for the case that is a linear space with hyperbolic incidence structure, the addition is not associative. is a K-loop or a Bruck loop.
Series of inscribed -gons and rank 3 configurations.
Some combinatorial properties of conics in the Hjelmslev plane
Special automorphisms of nets with Baer subnets
Subspace operations in affine Klingenberg spaces.
Ternary spaces, media, and Chebyshev sets
The Complexity and Construction of Many Faces in Arrangements of Lines and of Segments.
The Complexity of Many Cells in Arrangements of Planes and Related Problems.
The uniqueness of groups of type J4.
Topological Representation of Dual Pairs of Oriented Matroids.
Une axiomatisation au premier ordre des arrangements de pseudodroites euclidiennes
Nous définissons une structure logique permettant de représenter les classes d’homéomorphismes des arrangements de pseudodroites du plan euclidien. Nous donnons une axiomatisation finie du premier ordre de la réalisabilité des arrangements de pseudodroites.
"What Is a Complex Matroid?"
Решетчатые движения евклидовой плоскости
Сильно минимальные счетно категоричные теории. II.