1. V. E. Barskii, V. M. Gindilis, and E. N. Khachaturov, Ontogenez, No. 5, 482 (1970).
2. V. Ya. Brodskii, I. B. Bukhvalov, N. V. Nechaeva, et al., Ontogenez, No. 6, 587 (1970).
3. K. P. Ganina, K. A. Gudim-Levkovich, L. P. Lysyuk, et al., Tsitologiya, No. 8, 981 (1968).
4. M. L. Efimov, V. R. Kovalenko, and G. S. Vasil'eva, Vopr. Onkol., No. 3, 31 (1970).
5. Ts. G. Masevich, Precancerous Diseases of the Stomach [in Russian], Leningrad (1969), p. 163.