1. L. D. Antonaccio, N. A. Pereira, B. Gilbert, H. Vorbrueggen, H. Budzikiewicz, J. M. Wilson, L.J. Durham andC. Djerassi, J. Am. chem. Soc.84, 2161 (1962).
2. G. Spiteller etM. Spiteller-Friedmann, Mh. Chem.93, 795 (1962).
3. H. Budzikiewicz, D. H. Williams etC. Djerassi,Structure Elucidation of Natural Products by Mass Spectrometry (Holden-Day, Inc., San Francisco 1964), Vol. 1, p. 77.
4. J. Lederberg,Computation of Molecular Formules for Mass Spectrometry (Holden-Day, San Francisco 1964).
5. R. M. Silverstein etG. C. Bassler,Spectrometric Identification of Organic Compounds (J. Wiley et Sons, Inc., New York 1967), p. 168.