Collect. Czech. Chem. Commun.
1978, 43, 3210-3226
https://doi.org/10.1135/cccc19783210
On the validity of the "cis/trans" lactone rule for allylic coupling constants of the α-exomethylene protons in natural sesquiterpenic α-exomethylene γ-lactones
Zdeněk Samek