Columbia subject headings:
Harvard subject headings:
Hokkaido (Japan)--Economic conditions.
Hokkaido (Japan)--History.
Hokkaido (Japan)--Social conditions.
Labor movement--Japan--Hokkaido--History.
Labor--Japan--Hokkaido--History.
Working class--Japan--Hokkaido--History.
Princeton subject headings:
Hokkaido (Japan)--Economic conditions.
Hokkaido (Japan)--History.
Hokkaido (Japan)--Social conditions.
Labor--Japan--Hokkaido--History.