Joseph Burtt and William Cadbury
Cocoa controversy
Chocolate island
Sleeping sickness and slavery
Luanda and the coast
The slave route
Mozambican miners
Cadbury, Burtt, and Portuguese Africa
Cocoa and slavery.
Chocolate islands : cocoa, slavery, and colonial Africa by Catherine Higgs. ISBN 9780821420065. Published by Ohio University Press in 2012. Publication and catalogue information, links to buy online and reader comments.