On moduli of expansion of the duality mapping of smooth Banach spaces.
On Moser's Problem of Accommodating Closed Curves in Triangles.
On multiple nuclei and a conjecture of Lunelli and Sce.
On n-ary equivalence relations and their application to geometry [Book]
On non-localized oriented angles
On Norm Three Vectors in Integral Euclidean Lattices. I.
On one construction of all quasifields of order 9
On opposite angle points in isotropic triangle geometrics. (Zu den Winkelgegenpunkten der isotropen Dreiecksgeometrie.)
On optimal linear codes over .
On orthogonality in nets
On ovoids of .
On pairs of metrics invariant under a cocompact action of a group.
On permutable quadratic inversions in plane with two common singular points
On perspectivities in incidence geometries of grade n
On Planes of Lenz-Barlotti Class I 6 and Planes of Lenz Class III.
On Polyhedra with Transitivity Properties.
On projective planes of order 20
On Projective Planes of Order Twelve and Twenty.
On Projective Planes of Type (5, m).
On propellers from triangles.