Columbia subject headings:
Harvard subject headings:
Economics--Dictionaries
Political science--Dictionaries
United States--History--Dictionaries.
United States--Politics and government--Dictionaries.
United States--Politics and government.
Princeton subject headings:
Dictionaries.
Economics--Dictionaries.
Political science--Dictionaries.
United States--History--Dictionaries.
United States--Politics and government--Dictionaries.