Columbia subject headings:
Agriculture--United States--Statistics--Congresses.
United States--Census, 1990--Congresses.
United States--Population--Statistics--Congresses.
Harvard subject headings:
Agriculture--United States--Statistics--Congresses.
Minorities--United States--Statistics--Congresses.
United States--Census, 1990--Congresses.
United States--Population--Statistics--Congresses.
Princeton subject headings:
Agriculture--United States--Statistics--Congresses.
United States--Census, 21st, 1990--Congresses.
United States--Population--Statistics--Congresses.