On seven points in the boundary of a plane convex body in large relative distances.
On the Complexity of a Single Cell in Certain Arrangements of Surfaces Related to Motion Planning.
On the diffeomorphic type of the complement to a line arrangement in a projective plane
We show that the diffeomorphic type of the complement to a line arrangement in a complex projective plane P 2 depends only on the graph of line intersections if no line in the arrangement contains more than two points in which at least two lines intersect. This result also holds for some special arrangements which do not satisfy this property. However it is not true in general, see [Rybnikov G., On the fundamental group of the complement of a complex hyperplane arrangement, Funct. Anal. Appl., 2011,...
On the Zone of a Surface in a Hyperplane Arrangement.
Oriented Matroids with Few Mutations.