1. P. S. Bailey in ‘Ozonation in Organic Chemistry’, Academic Press, New York, vol. 1 (1978), vol. 2 (1982).
2. L. F. Fieser and M.Fieser, Steroids, Reinhold, New York, 1959, ch. 6 and 13.
3. E. P. Oliveto in ‘Organic Reactions in Steroid Chemistry’, ed. J. Fried and J. A. Edwards, Van Nostrand Reinhold Co., New York, 1972, vol. 2, p. 158.
4. G. Ourisson , P.Crabbe, and O. R.Rodig in ‘Tetracyclic Triterpenes’, Hermann, Paris, 1964, ch. 2;
5. Über die Konstitution des Stigmasterins