Summary
— A family of finite generalized quadrangles, including those of type T2 * (O), is characterized in this paper by a simple axiom on geometries belonging to the diagram C2.c. Adding one more axiom, a characterization of 2 * (O) is also obtained.
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Del Fra, A., Pasini, A. C2·c Geometries and Generalized Quadrangles of Order (s − 1, s + 1). Results. Math. 22, 489–508 (1992). https://doi.org/10.1007/BF03323102
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DOI: https://doi.org/10.1007/BF03323102