1. Ambrus, J.L., Feltz, E.T., Grace, J.T. and Owens, G. 1963. Natl Cancer Inst. Mono., 10, 447–453
2. Ambrus, J.L. and Strandstrom, H.V. 1966. Nature, 211, 876
3. Anderson, C.R., Spence, L.P., Downs, W.G. and Aitken, T.H.G. 1960. Amer. J. Trop. Med. Hyg., 9, 78–80
4. Andrewes, C. and Pereira, H.G. 1967. Viruses of vertebrates, 2nd ed., Williams and Wilkins Co., Baltimore
5. Arita, I. and Henderson, D.A. 1968. Bull. Org. Mond. Sante., 39, 277–283