Columbia subject headings:
Harvard subject headings:
Labor movement--History--20th century.
Labor unions--History--20th century.
Metal-workers--History--20th century.
Shipbuilding industry--History--20th century.
Princeton subject headings:
Academic theses.
Labor movement--History--20th century.
Labor unions--History--20th century.
Metal-workers--History--20th century.
Shipbuilding industry--History--20th century.