Columbia subject headings:
Harvard subject headings:
Niebuhr, Reinhold, 1892-1971
Ruether, Rosemary Radford.
Social change--History--20th century.
Social ethics--History--20th century.
Princeton subject headings:
Niebuhr, Reinhold, 1892-1971.
Ruether, Rosemary Radford.
Social change--History--20th century.
Social ethics--History--20th century.