1. Gottschalk, A. in The Viruses Vol. 3 (eds Burnet, F. M. & Stanley, W. M.) 51–61 (Academic, New York, 1959).
2. Stone, J. D. Br. J. exp. Path. 32, 367–376 (1951).
3. Choppin, P. W. & Tamm, I. J. exp. Med. 112, 895–920 (1960).
4. Carroll, S. M., Higa, H. H. & Paulson, J. C. J. biol. Chem. 256, 8357–8363 (1981).
5. Wilson, I. A., Skehel, J. J. & Wiley, D. C. Nature 289, 368–373 (1981).