Here are some interesting and relevant publications that I used for my thesis and Websites that are interesting for starting to get to know cacao:

UN IPCC Fifth Assessment Report (2014) – Summary for Policy Makers

Grivetti, L.E. and Shapiro, H.Y., 2011. Chocolate: history, culture, and heritage. John Wiley & Sons

Astrid Gutsche, 2014,  Los guardianes del cacao. Planeta

G. Wood, R. Lass, 2001, Cocoa 4th Edition. Wiley-Blackwell This site is part of an exhibition that ran at Cornell University, it gives a very good overview about the history of cacao