1. Tornasi, T. B. and Bienenstock, J., in Advances in Immunology (Edited by Dixon, F. J., Jr. and Kunkel, H. G.) Vol. 9, p. 1, Academic Press, New York, 1968.
2. Kaltreider, H. B. and Chan, M.K.L., J. Immunol. 116: 423, 1976.
3. Amoss, H. L. and Taylor, E., J. Exp. Med. 25: 507, 1917.
4. Bull, C. G. and McKee, C. M., Am. J. Hyg. 9: 490, 1929.
5. Rossen, R. D., Kasel, J. A. and Couch, R. B., Prog. Med. Virol. 13: 194, 1971.