1. Bastian, F. O., Am. J. Clin. Path. 61, 711 (1974)
2. Bennet, A. G., Ann. Int. Med. 19, 111 (1943)
3. Christensen, H. E., Sorensen, K. H., Acta path, microbial. Scand. Sect. A 80, 12ß (1972)
4. Fondimare, A., Bcumard, M. C., Deshayes, P., Rev. Rhumat. 43, 144 (1976)
5. Malmström, M., Husby, G., Scand. J. Rheumat. 4, 186 (1975)