Columbia subject headings:
Asylums--United States.
Prisons--United States--Statistics.
United States--Census, 1940.
Harvard subject headings:
Asylums--United States.
Prisons--United States--Statistics.
United States--Census, 1940.
Princeton subject headings:
Asylums--United States.
Prisons--United States--Statistics.
United States--Census, 1940.