Columbia subject headings:
Harvard subject headings:
Coffee industry--Germany--Hamburg--History--20th century.
Green products--Germany--Hamburg--History--20th century.
Merchants--Germany--Hamburg--History--20th century.
Princeton subject headings:
Coffee industry--Germany--Hamburg--History--20th century.
Green products--Germany--Hamburg--History--20th century.
Merchants--Germany--Hamburg--History--20th century.