1. Kaneko H, et, al. The Aroma of Cigar Tobacco. Part I. Isolation of 2-Hydroxy-2,6,6-trimethylcyclohexylidene-1-acetic Acid Lactone (Dihydroactinidiolide) from Ether Extract of Cigar Leaves. Agricultural and Biological Chemistry. 1968 Jou; 32(11): 1337-40.2. Bosser A, et, al. A Simple Way to (±)-Dihydroactinidiolide from β-Ionone Related to the Enzymic Co-oxidation of β-Carotene in Aqueous Solution. Biotechnology Progress. 1995 Jou; 11(6): 689-92.