... were recorded on a VG 12-253 spectrometer, electron impact (EI) at 70 eV and chemical ionization (CI ... Friedel-Crafts Chemistry, ed. GA Olah, Wiley-Interscience, New York, 1973 Search PubMed . M. Spagnol, L. Gilbert and D. Alby, in The Roots of Organic Development, eds. ...