The minimal model of a Minkowski plane is miquelian. It is isomorphic to the Minkowski plane with (field ). An astonishing result is Theorem (Heise): Any Minkowski plane of even order is miquelian. Remark: A suitable stereographic projection shows: is isomorphic to the geometry of the plane sections on a hyperboloid of one sheet (quadric of index 2) in projective 3-space over field . Remark: There are a lot of Minkowski planes that are not miquelian (s. weblink below). But there are no "ovoidal Minkowski" planes, in difference to Möbius and Laguerre planes. Because any quadratic set of index 2 in projective 3-space is a quadric (see quadratic set). See also Conformal geometry References Walter Benz (1973) Vorlesungen über Geomerie der Algebren, Springer Francis Buekenhout (editor) (1995) Handbook of Incidence Geometry, Elsevier External links Benz plane in the Encyclopedia of Mathematics Lecture Note Planar Circle Geometries, an Introduction to Moebius-, Laguerre- and Minkowski Planes Planes (geometry)