1. A. G. Babaeva and R. R. Tlel'ka, Byull. Éksperim. Biol. i Med., No. 6, 90 (1968).
2. N. A. Kraskina, Function of Lymphoid Tissue in the Formation of Postvaccinal Immunity [in Russian], Moscow (1968).
3. V. I. Levenson and N. A. Kraskina, Byull. Éksperim. Biol. i Med., No. 12, 64 (1962).
4. L. N. Fontalin, L. A. Pevnitskii, and N. A. Kraskina, Byull. Éksperim. Biol. i Med., No. 11, 108 (1967).
5. E. G. Bade, I. L. Sadnik, C. Pilgrin, et al., Exp. Cell. Res.,44, 676 (1966).