A group-theoretic characterization of classical unitals
The authors prove the following beautiful characterization of the classical unitals: A unital embedded in \(\Pi=PG(2,q^2)\) is classical (i.e., induced by a unitary polarity) if and only if it is fixed by a subgroup of order \(q^2-q+1\) of a Singer group for \(\Pi\).
scientific article; zbMATH DE number 1437110