Columbia subject headings:
African Americans--Social conditions.
Black people--Brazil--History.
Brazil--Race relations.
Slavery--Brazil--History.
Slavery--United States--History.
United States--Race relations.
Harvard subject headings:
African Americans--Social conditions
Black people--Brazil--History
Brazil--Race relations
Slavery--Brazil--History
Slavery--United States--History
United States--Race relations
Princeton subject headings:
African Americans--Social conditions.
Black people--Brazil--History.
Brazil--Race relations.
Slavery--Brazil--History.
Slavery--United States--History.
United States--Race relations.