Extended generalized quadrangles
This very interesting and excellent paper studies extended generalized quadrangles (EGQ) in a systematic way. Roughly, an EGQ is a (point, pair of collinear points, line)-geometry where the residue of every point is a generalized quadrangle. The paper is written in the style of a survey paper, starting off from scratch. The authors subdivide the class of EGQ in some subclasses such as ``uniform'', ``strongly uniform'', ``extensions of even CF type'', etc... and they show some classification results. In a final section, they gather all known interesting examples of EGQ. Along the way, there is also a section containing new results on diameter bounds. Both beginners and experts on the subject will enjoy this paper.
scientific article; zbMATH DE number 4151237