1. R.J.R. Abel, D. Combe, W.D. Palmer, Bhaskar Rao designs and the groups of order 12, Australas. J. Combin., to appear.
2. PBD-closure;Bennett,1996
3. Design Theory, 2nd Edition;Beth,1999
4. Bhaskar Rao designs and the alternating group A4;Combe;Australas. J. Combin.,2001
5. Generalized Bhaskar Rao designs of block size 3 over Z4;de Launey;Ars Combin.,1985