On a generalized Minkowski inequality and its relation to dominates for t-norms.
On a generalized stereographic projection. (Zur verallgemeinerten stereographischen Projektion.)
On a geometric inequality by J. Sándor.
On a Model of Plane Geometry.
On a Paschian Condition for Linear Spaces.
On a planar construction of quasigroups
On a problem for isometric mappings of posed by Th. M. Rassias.
On a quasilinear elliptic equation and a Riemannian metric invariant under Möbius transformations.
On a quasilinear elliptic equation and a Riemannian metric invariant under Möbius transformations. (Summary).
On a special class of Frobenius groups admitting planar partitions.
On a system of equations related to bicentric polygons.
On affine planes non-extensible to Laguerre planes and some related problems
Some examples of affine planes non-extensible to a Laguerre plane are studied and conditions for the uniqueness of a Laguerre extension are given.
On an application of the theorem of Apollonius
On an upper bound for the deviations from the mean value.
On analytic models of synthetic differential geometry
On Averaging Multisets.
On B. Segre's construction of an ovaloid
On Baer Subspaces of Finite Projective Spaces.
On Blocking Sets in Affine Hjelmslev Planes
ACM Computing Classification System (1998): G.2.1.We prove that the minimum size of an affine blocking set in the affine plane AHG ...This research has been supported by the Scientific Research Fund of Sofia University under Contract No 109/09.05.2012.
On Brocard points in the isotropic plane.