1. A. P. Dyban, Ontogenez,8, 582 (1977).
2. I. I. Karuzina and A. I. Archakov, in: Modern Methods in Biochemistry [in Russian], Moscow (1977), p. 49.
3. Technical Instructions for Testing of the Teratogenic and Embryotoxic Activity of New Therapeutic Substances [in Russian], Moscow (1972).
4. L. S. Persianinov, A. P. Kiryushchenkov, and A. M. Skosyreva, Arkh. Anat., No. 4, 93 (1974).
5. N. Brock and H. J. Hohorst, Cancer (Philadelphia),20, 900 (1967).