1. V. V. Vinogradov, K. A. Mandrik, and Yu. M. Ostrovskii, Izv. Akad. Nauk Belor. SSR, No. 6, 68 (1973).
2. V. V. Vinogradov et al., Ukr. Biokhim. Zh., No. 4, 421 (1976).
3. N. I. Kalabukhov, Periodic Seasonal and Annual Body Changes in Rodents, Their Causes and Consequences [in Russian], Leningrad (1969).
4. N. A. Yudaev, B. V. Pokrovskii, and T. N. Protasova, in: Biochemistry of Hormones and Hormonal Regulation [in Russian], Moscow (1976), p. 350.
5. P. Ashman and G. Seed, Comp. Biochem. Physiol.,45, 365 (1973).