de Kraker, J., Franssen, M. C. R., Dalm, M. C. F., de Groot, A., & Bouwmeester, H. J. (2001). Biosynthesis of Germacrene A Carboxylic Acid in Chicory Roots. Demonstration of a Cytochrome P450 (+)-Germacrene A Hydroxylase and NADP(+)-Dependent Sesquiterpenoid Dehydrogenase(s) Involved in Sesquiterpene Lactone Biosynthesis. American Society of Plant Physiologists.

de Kraker, Jan-Willem, Maurice C. R. Franssen, Marcella C. F. Dalm, Aede de Groot, và Harro J. Bouwmeester. Biosynthesis of Germacrene A Carboxylic Acid in Chicory Roots. Demonstration of a Cytochrome P450 (+)-Germacrene A Hydroxylase And NADP(+)-Dependent Sesquiterpenoid Dehydrogenase(s) Involved in Sesquiterpene Lactone Biosynthesis. American Society of Plant Physiologists, 2001.

de Kraker, Jan-Willem, et al. Biosynthesis of Germacrene A Carboxylic Acid in Chicory Roots. Demonstration of a Cytochrome P450 (+)-Germacrene A Hydroxylase And NADP(+)-Dependent Sesquiterpenoid Dehydrogenase(s) Involved in Sesquiterpene Lactone Biosynthesis. American Society of Plant Physiologists, 2001.