An interesting question posed by Cofman [Atti Accad. Naz. Lincei, (8) 43 (1967)] is the following: ”Let Π be a finite plane with a subset O of points admitting a collineation group G which maps O onto itself and induces a doubly transitive collineation group on the points of O. What can we say about the plane, the set O and the collineation group G?”. A… (More)

The embedding of a Ree Unital R(q) in a finite projective plane of order up to q4 is investigated when the Ree group is induced on R(q) by a collineation group of . In particular, it is shown that such a embedding is not admissible for q = 3, extending in this way a result of Lüneburg dating back to 1965.