1. ?Carbon-13 NMR Spectroscopy?, Academic Press 1972.
2. See e. g. in ?Topics in Carbon-13 NMR Spectroscopy? (Ed. Levy) 1, 53 (1974).
3. Carbon-13 chemical shifts of 1-substituted norbornanes
4. see also & J. chem. Soc. Perkin II, 1975, 539.
5. J. chem. Soc. Perkin II, 1976, 1579.