1. Adler, W., Takiguchi, T., and Smith, R. T., 1971, Effect of age upon primary alloantigen recognition by mouse spleen cells, J. Immunol. 107: 1357–1362.
2. Alexander, P., 1967, The role of DNA lesions in processes leading to aging in mice, Symp. Soc. Exp. Biol. 21: 29–50.
3. Alexopoulos, C., and Babitis, P., 1976, Age dependence of T lymphocytes, Lancet 1: 426.
4. Archer, O. K., and Pierce, J. C., 1961, Role of thymus in development of the immune response, Fed. Proc. Fed. Am. Soc. Exp. Biol. 20: 26.
5. Archer, O. K., Pierce, J. C., Papermaster, B. W., and Good, R. A., 1962, Reduced antibody response in thymectomized rabbits. Nature (London) 195: 191–192.