Subplanes of projective planes of order 121
One of the major open questions in the theory of projective planes is the existence of a non-Desarguesian plane of prime order. The smallest open prime is \(p= 11\). In this paper the authors start with a Veblen-Wedderburn plane and a Hughes plane of order \(11^2\) and study subplanes generated by quadrangles. In particular Baer subplanes are of interest. The outcoming is that all such Baer planes are Desarguesian. Hence if one of these projective planes contains a Baer subplane which is non-Desarguesian, then it is not generated by a quadrangle.
scientific article; zbMATH DE number 5808434