Columbia subject headings:
Slave trade--Denmark--History.
Slave trade--Ghana--History.
Slave trade--Norway--History.
Slave trade--West Indies.
Harvard subject headings:
Slave trade--Denmark--History.
Slave trade--Ghana--History.
Slave trade--Norway--History.
Slave trade--West Indies.
Princeton subject headings:
Slave trade--Denmark--History.
Slave trade--Ghana--History.
Slave trade--Norway--History.
Slave trade--West Indies--History.