1. Memorandum from a WHO meeting, 1982, Immunological research in tuberculosis, Bull. WHO 60:723–727.
2. Stead, W. W., 1967, Pathogenesis of a first episode of chronic pulmonary tuberculosis in man: Recrudescence of residuals of the primary infection or exogenous reinfection?, Am. Rev. Respir. Dis. 95:729–745.
3. West, J. B., 1962, Regional differences in gas exchange in the lungs of erect man, J. Appl. Physiol. 17:893–898.
4. Opie. E. L. ,and Aronson, J. D., 1927, Tubercle bacilli in latent tuberculous lesions and in lung tissue without tuberculous lesions, Arch. Pathol. Lab. Med. 4: 1–21.
5. Canetti, G. ,1972, Endogenous reactivation and exogenous reinfection: Their relative importance with regard to the development of non-primary tuberculosis, Bull. Int. Natl. Union Tuberc. 47:116–122.