Columbia subject headings:
Harvard subject headings:
Europe--Politics and government.
Gussstahlfabrik Fried. Krupp (Essen)
Krupp family.
Krupp'ache gusstahlfabrik, Essen.
Ordnance--Manufacture
Princeton subject headings:
Europe--Politics and government.
Gussstahlfabrik Fried. Krupp (Essen)
Krupp family.
Ordnance--Manufacture.