Designs, Codes and Cryptography

, Volume 64, Issue 3, pp 255–263 | Cite as

A geometric proof of a theorem on antiregularity of generalized quadrangles

Open Access


A geometric proof is given in terms of Laguerre geometry of the theorem of Bagchi, Brouwer and Wilbrink, which states that if a generalized quadrangle of order s > 1 has an antiregular point then all of its points are antiregular.


Antiregularity Generalized quadrangles Codes Laguerre geometry 

Mathematics Subject Classification (2000)

51B15 51E12 51E22 



The authors would like to thank the reviewers for their suggestions which lead to a shortening of the proof of our main result.

Open Access

This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.


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Copyright information

© The Author(s) 2011

Authors and Affiliations

  1. 1.Department of MathematicsThe University of Hong KongHong KongChina

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