1. E.O. Afoakwa, Chocolate Science and Technology (Wiley, West Sussex, 2010)
2. M.A. Barel, D. Leon, J.C. Vincent, Café Cacao (Francia) 29(4), 277–286 (1985)
3. G. Vernin, Chemistry of Heterocyclic Compounds in Flavours and Aromas (Wiley, Ellis Horwood, 1982)
4. A. Gallois, Sci Aliment. 4, 145 (1984)
5. R. Silwar, Cafe Cacao (Francia) 32(3), 243–250 (1988)