Columbia subject headings:
Harvard subject headings:
Internal security--Japan--History--Sources.
Labor movement--Japan--History--Sources.
Police--Japan--History--20th century--Sources.
Socialism--Japan--Sources.
Working class--Political activity--Japan--History--20th century--Sources.
Princeton subject headings:
Internal security--Japan--History--Sources.
Labor movement--Japan--History--Sources.
Police--Japan--History--20th century--Sources.
Socialism--Japan--History--Sources.
Working class--Political activity--Japan--History--20th century--Sources.