1. Trentin, J.J. in Regulation of Haematopoiesis Vol.4 (ed. Gordon, A.S.) (Appleton-Century-Crofts, New York, 1970).
2. Wolf, N.S. Tissue Kinetics 11, 335 (1978).
3. Till, J.E., McCulloch, E.A. & Siminovitch, L. Proc. natn. Acad. Sci. U.S.A. 51, 29 (1964).
4. Humphries, R.K., Eaves, A.C. & Eaves, C.J. Proc. natn. Acad. Sci. U.S.A. 78, 3629 (1981).
5. Gregory, C.J. & Henkelman, R.M. in Experimental Haematology Today (eds Baum, S.J. & Ledney, G.D.) (Springer, New York, 1977).