Columbia subject headings:
History--Philosophy.
Sociology.
Sorokin, Pitirim Aleksandrovich, 1889-1968.
Harvard subject headings:
History--Philosophy
Sociology.
Sorokin, Pitirim Aleksandrovich, 1889-1968
Princeton subject headings:
History--Philosophy.
Sociology.
Sorokin, Pitirim Aleksandrovich, 1889-