1. E.S. Airapetiants and V.L. Balakshina, in the book: Transactions of the Leningrad Society of Natural History In Russian. Vol. 62, No. 1–2, 141–145 (Leningrad-Moscow, 1933).
2. A.V. Tonkikh, Russk. fiziol. Zhur. No. 1–2, 85–93 (1927).
3. A.V. Tonkikh, Fiziol. Zhur. SSSR No. 1, 11–18 (1930).
4. I.M. Tylevich and B.S. Rabinovich, in the book: The Mechanism of Pathologic Reactions In Russian. ed. 11–15, 77–80 (1949).
5. C.G. Bernhard, Res. Publ. Ass. Nerv. and Ment. Dis. 30, 68–86 (1952).