1. Colowick, S. P. and Kaplan, N. O. (1978) Methods Enzymol., 51.
2. Muller, M. M., Kaiser, E. and Seegmiller, J. E. (1977) Advances in Experimental Medicine and Biology. Purine Metabolism in Man — II, Plenum Press, New York, vol. 76A and 76B.
3. Kornberg, A. (1980) DNA Replication. Freeman, San Francisco.
4. Henderson, J. F. and Paterson, A. R. P. (1973) Nucleotide Metabolism, Academic Press, New York.
5. Jensen, K. F. (1983) in Metabolism of Nucleotides, Nucleosides and Nucleobases in Microorganisms (ed. A. Munch-Petersen), Academic Press, London, p. 1.