Columbia subject headings:
Occupations--Law and legislation--United States--Congresses.
Occupations--Licenses--United States--Congresses.
Harvard subject headings:
Occupations--Law and legislation--United States--Congresses.
Occupations--Licenses--United States--Congresses.
Occupations--United States--Licenses--Congresses.
Princeton subject headings:
Occuaptions--Licenses--United States--Congresses.
Occupations--Law and legislation--United States--Congresses.