1. Nossal, G.J. V. and Ada, G. L. “Antigens, Lymphoid Cells and the Immune Response”. Academic Press, New York and London (1971).
2. Raff, M.D., Sternberg, M., and Taylor, R.B. (1970) Nature, 225, 553.
3. Bankhurst, A.D., Warner, N. L. and Sprent, J. (1971) J. Exp. Med. 134, 1005.
4. Nossal, G. J. V., Warner, N. L., Lewis, H. and Sprent, J. (1972) J.Exp. Med. 135, 405.
5. Till, J.E., McCullogh, E.A. and Siminovitch, L. (1964) Proc. Nat. Acad. Sci. U.S. 51, 29.