1. S. Gorog, Quantitative Analysis of Steroids, Elsevier, Amsterdam-New York (1983).
2. A. S. Efimov, P. N. Bodnar, and B. A. Zelinskii, Engicronology [in Russian], Kiev (1983), pp. 245–250.
3. M. F. Mashkovskii, Drugs [in Russian], 8th edn., Part 1, Moscow (1978), pp. 571–588.
4. G. M. Rodchenkov, V. P. Uralets, and V. A. Semenov, Zh. Anal. Khim.,42, 1678–1683 (1987).
5. D. S.-L. Au, J. O. Runikis, F. S. Abbott, and R. W. Burton, J. Pharm. Sci.,70, No. 8, 917–923 (1981).