Columbia subject headings:
Labor unions and communism--United States--History--20th century.
Merchant mariners--Labor unions--United States--History--20th century.
Stevedores--Labor unions--United States--History--20th century.
Strikes and lockouts--Merchant marine--United States--History--20th century.
Strikes and lockouts--Stevedores--United States--History--20th century.
Syndicalism--United States--History--20th century.
Harvard subject headings:
Labor unions and communism--United States--History--20th century.
Merchant mariners--Labor unions--United States--History--20th century.
Stevedores--Labor unions--United States--History--20th century.
Strikes and lockouts--Merchant marine--United States--History--20th century.
Strikes and lockouts--Stevedores--United States--History--20th century.
Syndicalism--United States--History--20th century.
Working class--United States--History--20th century
Princeton subject headings:
Labor unions and communism--United States--History--20th century.
Merchant mariners--Labor unions--United States--History--20th century.
Stevedores--Labor unions--United States--History--20th century.
Strikes and lockouts--Merchant marine--United States--History--20th century.
Strikes and lockouts--Stevedores--United States--History--20th century.
Syndicalism--United States--History--20th century.