Columbia subject headings:
Coal miners--Labor unions--United States.
Coal trade--United States.
Collective bargaining--Coal mining industry--United States.
Collective labor agreements--Coal mining industry--United States.
Industrial relations--United States.
Harvard subject headings:
Coal miners--Labor unions--United States.
Coal trade--United States.
Collective bargaining--Coal mining industry--United States.
Collective labor agreements--Coal mining industry--United States.
Industrial relations--United States
Princeton subject headings:
Coal miners--Labor unions--United States.
Coal trade--United States.
Collective bargaining--Coal mining industry--United States.
Collective labor agreements--Coal mining industry--United States.
Industrial relations--United States.