Columbia subject headings:
Slave trade--Africa.
Slave trade--Brazil.
Slavery and the church.
Slavery--Law and legislation--Portugal.
Harvard subject headings:
Slave trade--Africa
Slave trade--Brazil.
Slavery and the church
Slavery--Law and legislation--Portugal.
Princeton subject headings:
Slave trade--Africa.
Slave trade--Brazil.
Slavery and the church.
Slavery--Law and legislation--Portugal.