1. Abrams, G. D., Bauer, H., and Sprinz, H., 1963, Influence of the normal flora on mucosal morphology and cellular renewal in the ileum. A comparison of germfree and conventional mice, Lab. Invest. 12:355.
2. Alexander, P., 1957, Atomic Radiation and Life, Penguin Press, London.
3. Andersson, J., Sjöberg, O., and Möller, G., 1972, Induction of immunoglobulin and antibody synthesis in vitro by lipopolysaccharides, Eur. J. Immunol 2: 349.
4. Argyris, B. F., and Horowitz, M., 1976, Cell interaction in tumor allograft immunity, Transplantation 22: 112.
5. Arnason, B. G., Salomon, J. C., and Grabar, P., 1964, Anticorps antifoie et immunoglobulines seriques chez les souris classiques et axeniques; étude comparative après necrose hepatique aigue provoquée par le tetrachlorure de carbone, C.R. Acad. Sci 259: 4882.