Columbia subject headings:
Harvard subject headings:
B. Sprengel & Co.--History.
Chocolate candy--Germany--Hannover--History.
Chocolate factories--Germany--Hannover--History.
Chocolate industry--Germany--Hannover--History.
Princeton subject headings:
B. Sprengel & Co.--History.
Chocolate candy--History.
Chocolate factories--Germany--Hannover--History.
Chocolate industry--History.