Columbia subject headings:
Labor supply--United States--Statistics--Periodicals.
Unemployed--United States--Statistics--Periodicals.
Harvard subject headings:
Labor supply--United States--Statistics--Periodicals.
Unemployed--United States--Statistics--Periodicals.
Princeton subject headings:
Labor supply--United States--Statistics--Periodicals.
Periodicals.
Statistics.
Unemployed--United States--Statistics--Periodicals.