1. N. P. Gundobzin, Special Features of Childhood [in Russian], St. Petersburg (1906), p. 138.
2. G. A. Gurevich, A. A. Klimentova, and I. N. Kokorin, in the book: Problems in Infectious Pathology and Immunology [in Russian], Moscow (1963), p. 8.
3. V. K. Demidova, Abstracts of Proceedings of the First Scientific Conference of Morphologists of the Republics of Central Asia and Kazakhstan [in Russian], Dushanbe (1960), p. 109.
4. D. A. Zhdanov, Abstracts of Proceedings of the First Scientific Conference of Morphologists of the Republics of Central Asia and Kazakhstan [in Russian], Dushanbe (1960), p. 125.
5. N. F. Komotskii, in the book: Basis of the Study of Microscopic Anatomy of Man and Animals [in Russian], Vol. 2, St. Petersburg (1888), p. 427.