Terpenoids - XCVI: Dehydration reaction of guaiol and dihydroguaiols and transformation of 1α, 5α-dihydroguaiol to 1α, 5α-hexahydrodehydrocostus lactone - Kadival,M.V.; Nair,M.SR.; Bhattacharya,S.C. (Tetrahedron, 1967)