1. Korovin, E.P.: Illustrated Monograph of the Genus Ferula. Tashkent: 1947. See ref. 28.
2. Saidkhodzhaev, A.I.: Sesquiterpene Derivatives of the Genus Ferula. Khim Chem Abstr. 4, 437 (1979); Chem. Abstr., 92, 76670p (1980).
3. Kir’yalov, N.P.: Coumarins from Plants of the Genus Ferula. Tr. Botan. Inst., Akad. Nauk SSSR, Ser. 5, Rast. Syr’e, 12, 82 (1965)
4. Kir’yalov, N.P.: Coumarins from Plants of the Genus Ferula. Tr. Botan. Inst., Akad. Chem. Abstr., 59, 5255h (1966).
5. Kir’yalov, N.P., and V.Yu. Bagirov: Structure of Karatavikin. Khim. Prir. Soedin., 3, 223 (1967)