Columbia subject headings:
Labor--Poland.
Poland--History--1945-1980.
Harvard subject headings:
Poland--Politics and government--1945-1980
Strikes and lockouts--Poland
Working class--Poland.
Princeton subject headings:
Poland--Social conditions.
Riots--Poland--Gdańsk.
Riots--Poland--Szczecin.
Strikes and lockouts--Poland--Gdańsk.
Strikes and lockouts--Poland--Szczecin.