Ein "affiner" Beweis des Satzes von v. Staudt - Schleiermacher.
Eine geometrische Kennzeichnung linearer Abbildungen.
Eine Verallgemeinerung des Satzes von Dandelin.
Embeddings of projective Klingenberg planes in the projective space PG(5,).
Extending Nearaffine Planes to Hyperbola Structures
H. A. Wilbrink [Geom. Dedicata 12 (1982)] considered a class of Minkowski planes whose restrictions, called residual planes, are nearaffine planes. Our study goes in the opposite direction: what conditions on a nearaffine plane are necessary and sufficient to get an extension which is a hyperbola structure.