Columbia subject headings:
Public opinion--Portugal--History.
Public opinion--Spain--History.
Slave trade--Central America--History.
Slave trade--Portugal--Public opinion--History.
Slave trade--Portugal--Religious aspects--Catholic Church.
Slave trade--South America--History.
Slave trade--Spain--Public opinion--History.
Slave trade--Spain--Religious aspects--Catholic Church.
Harvard subject headings:
Slave trade--Latin America.
Slavery--Spain--Justification.
Princeton subject headings:
Public opinion--Portugal--History.
Public opinion--Spain--History.
Slave trade--Central America--History.
Slave trade--Portugal--Public opinion--History.
Slave trade--Portugal--Religious aspects--Catholic Church.
Slave trade--South America--History.
Slave trade--Spain--Public opinion--History.
Slave trade--Spain--Religious aspects--Catholic Church.