1. V. Jha and N. L. Johnson, Rigidity in conical flocks, J. Combin. Theory Ser. A
73(1996), 60–76.
2. N. L. Johnson, The derivation of dual translation planes, J. Geom. 36(1989), 63–90.
3. N. L. Johnson and S. E. Payne, Flocks of Laguerre planes and associated geome-tries, Mostly Finite Geometries(ed. N. L. Johnson), Dekker, New York, 1997, 51–122.
4. M. Law and T. Penttila, BLT-sets over small fields II, preprint, (2000).
5. M. Law and T. Penttila, Some flocks in characteristic 3, preprint, 1999.