Columbia subject headings:
Harvard subject headings:
Appalachians (People)
Bituminous coal.
Coal miners--Kentucky
Coal miners--West Virginia
Coal mines and mining--United States
Kentucky--Social conditions.
Unemployed--United States
West Virginia--Social conditions.
Princeton subject headings:
Appalachians (People)
Bituminous coal.
Coal miners--Kentucky.
Coal miners--West Virginia.
Coal mines and mining--United States.
Kentucky--Social conditions.
Unemployed--United States.
West Virginia--Social conditions.