Columbia subject headings:
Arithmetic--History--Congresses.
Arithmetic--Textbooks--Congresses.
Business mathematics--Germany--History--Congresses.
Mathematics--Germany--History--Congresses.
Mercantile system--Germany--Congresses.
Harvard subject headings:
Arithmetic--History--Congresses.
Arithmetic--Textbooks--Congresses.
Business mathematics--Germany--History--Congresses.
Mathematics--Germany--History--Congresses.
Mercantile system--Germany--Congresses.
Princeton subject headings:
Arithmetic--History--Congresses.
Arithmetic--Textbooks--Congresses.
Business mathematics--Germany--History--Congresses.
Mathematics--Germany--History--Congresses.
Mercantile system--Germany--Congresses.
Textbooks.