1. A. Isaacs and J. Lindeman, Proc. Roy. Soc. B, 147, 258 (1957).
2. S. Pestka and S. Baron, Methods Enzymol., 78 (Interferons, Part A), 3 (1981).
3. 3 D. A. J. Tyrrell, Nature, 184, 452 (1959).
4. S. Baron, F. Dianzani, and G. J. Stanton, Tex. Rep. Biol. Med., 41, 1 (1982).
5. G. J. Galasso and J. K. Dunnick, Tex Rep. Biol. Med., 35, 479 (1977).