Columbia subject headings:
Bituminous coal industry--Germany--Saarland--History.
Bituminous coal--Germany--Saarland.
Coal mines and mining--Germany--Saarland--History.
Harvard subject headings:
Bituminous coal industry--Germany (West)--Saarland--History.
Bituminous coal industry--Germany--Saarland--History.
Bituminous coal--Germany (West)--Saarland.
Bituminous coal--Germany--Saarland.
Coal mines and mining--Germany (West)--Saarland--History.
Coal mines and mining--Germany--Saarland--History.
Princeton subject headings:
Coal mines and mining--Germany--Altenwald (Saarland)--History.
Coal mines and mining--Germany--Sulzbach (Saarland)--History.