Teilmengengraphen und projektive Räume.
The classification of subplane covered nets.
The elementary geometry of a triangular world with hexagonal circles.
The generating rank of the symplectic line-Grassmannian.
The Skew-Hyperbolic Motion Group of the Quaternion Plane.
The universal embedding of the near polygon .
The valuations of the near polygon G.
Topological and smooth unitals.
Two theorems on homomorphism of projective nets