Columbia subject headings:
Butterfield, Herbert, 1900-1979.
History--Philosophy.
International relations--Philosophy.
Political science--Philosophy.
Harvard subject headings:
Butterfield, Herbert, 1900-1979
History--Philosophy
International relations--Philosophy
Political science--Philosophy
Princeton subject headings:
Butterfield, Herbert, 1900-1979.
History--Philosophy.
International relations--Philosophy.
Political science--Philosophy.