1. Abt, A. F., and Bloom, W. (1928). J. Amer. med. Ass., 90, 2.
2. Abt, A. F., and Bloom, W. and Denenholz, E. J. (1936). Amer. J. Dis. Child., 51, 499.
3. Lectures on Pathology;Aschoff, L.;Virchows Arch,1924
4. Borrmann, R. (1907). Beitr. path. Anat., 40, 372.
5. Brill, N. E., and Mandelbaum, F. S. (1913). Amer. J. med. Sci., 146, 863.