Abstract:
It is shown that a pseudogeometrical graph $\Gamma$ for $\mathrm{GQ}(4,12)$, containing a $49$-coclique $\mathcal O$, is a point graph of generalized quadrangle. Furthermore, the subgraph $\Gamma-\mathcal O$ is strongly regular with parameters $(196,39,2,9)$. It is proved that a pseudogeometrical graph for partial geometry $\mathrm{pG}_2(5,32)$ is locally a $\mathrm{GQ}(4,8)$-graph.