Columbia subject headings:
Community organization--United States--History--20th century.
Social action--United States--History--20th century.
Social service--United States--History--20th century.
Harvard subject headings:
Community organization--United States--History--20th century.
Social action--United States--History--20th century.
Social service--United States--History--20th century.
Princeton subject headings:
Community organization--United States--History--20th century.
Social action--United States--History--20th century.
Social service--United States--History--20th century.