1. N. G. Bogdanov and N. I. Yalovaya, In the book: Problems in Vitaminology [in Russian], Barnaul (1959), pp. 41, 52.
2. B. I. Gol'dshtein, In the book: Vitamin K [in Russian], Moscow (1944), p. 96.
3. P. V. Lidina, Biokhimiya, No. 3, 209 (1951).
4. I. I. Matusis, In the book: Problems in Vitaminology [in Russian], Barnaul (1959), p. 4.
5. A. V. Palladin, In the book: Vitamin K [in Russian], Moscow, p. 5 (1944).