Thoughts upon the African slave trade

Some Historical Account of Guinea, Its Situation, Produce, and the General Disposition of Its Inhabitants An Inquiry into the Rise and Progress of the Slave Trade, Its Nature and Lamentable Effects

Observations on the slave trade and a description of some part of the coast of Guinea, during a voyage, made in 1787, and 1788, in company with Doctor A. Sparrman and Captain Arrehenius

A new account of Guinea, and the slave-trade

Turckse slavernie

Thoughts upon slavery