Related pagesIsomorphisms of partial linear spaces
Isomorphisms of linear spaces
Isomorphisms of projective planes
Two incidence structures are isomorphic if there exists an isomorphism from to . An isomorphism respects point rows and line pencils, i.e.
for all points p and all lines l.
Obviously, the set of all automorphisms of an incidence structure is a subgroup of the group
called the automorphism group of .