A t-(v, k, λ) design D is a pair of a set X of v points and a collection B of k-subsets ofX called blocks such that every t-subset of X is contained in exactly λ blocks. We oftendenote the design D by (X, B ). A design with no repeated block is called simple. Alldesigns in this note are simple. A Steiner system S(t, k, v) is a t-(v, k, λ) design withλ = 1. Two t-(v, k, λ) designs with the same point set are said to be disjoint if theyhave no blocks in common. Two t-(v, k, λ) designs are isomorphic if there is a bijectionbetween their point sets that maps the blocks of the first design into the blocks of thesecond design. An automorphism of a t-(v, k, λ) design D is any isomorphism of the designwith itself and the set consisting of all automorphisms of D is called the automorphismgroup Aut(D) of D.The well-known Steiner...