1. Extending t-designs;Alltop;J. Combin. Theory,1975
2. New 5-designs;Assmus;J. Combin. Theory,1969
3. Extending symmetric designs;Cameron;J. Combin. Theory,1973
4. Introduction to the Theory of Groups of Finite Order;Carmichael,1927
5. Some new 5-designs;Denniston;Bull. London Math. Soc.,1976