1. Duthie, J. J. R., in Textbook of the Rheumatic Diseases (edit. by Copeman, W. S. C), 175 (Livingstone, Edinburgh and London, 1964).
2. Gardner, D. L., Ann. Rheum. Dis., 19, 297 (1960).
3. Aoki, S., Merkel, M., Aoki, M., and McCabe, W. R., J. Lab. Clin. Med., 70, 204 (1967).
4. Aoki, S., Imamura, S., Aoki, M., and McCabe, W. R., New Engl. J. Med., 281, 1375 (1969).
5. Kunin, C. M., Beard, M. V., and Halmagyi, N. E., Proc. Soc. Exp. Biol. Med., 111, 160 (1962).