1. Edington, G. M. & Gilles, H. M. in Pathology in the Tropics, 57–59 (Edward Arnold, London, 1969).
2. Tacheuchi, A. & Phillips, B. P. Am. J. trap. Med. 24, 34–48 (1975).
3. Aust Kettis, A. A. & Sundqvist, K. G. Proc. Int. Conf. Amoebiasis, 324–333 (1976).
4. Cardella, C. J., Davies, P. & Allison, A. C. Nature 247, 46–48 (1974),
5. Schorlemmer, H. U. & Allison, A. C. Immunology 31, 781–788 (1976).