1. Cyclic block designs with block size 3;Colbourn;European J. Combin.,1981
2. On cyclic Steiner 2-designs;Colbourn;Ann. Discrete Math.,1980
3. Automorphisms of Steiner triple systems;Gardner,1987
4. Combinatorial Theory;Hall,1986
5. Halving the complete design;Hartman;Ann. Discrete Math.,1987