Columbia subject headings:
Harvard subject headings:
Competition--Germany--Congresses.
Food industry and trade--Germany--Congresses.
Grocery trade--Germany--Congresses.
Retail trade--Germany--Congresses.
Princeton subject headings:
Competition--Germany--Congresses.
Food industry and trade--Germany--Congresses.
Grocery trade--Germany--Congresses.
Retail trade--Germany--Congresses.