Columbia subject headings:
Middle class--Rhode Island--Providence--History.
Providence (R.I.)--History.
Providence (R.I.)--Social conditions.
Harvard subject headings:
Middle class--Rhode Island--Providence--History.
Providence (R.I.)--History.
Providence (R.I.)--Social conditions.
Princeton subject headings:
Middle class--Rhode Island--Providence--History.
Providence (R.I.)--History.
Providence (R.I.)--Social conditions.