- United States. Coal Commission ; Hammond, John Hays, 1855-1936
- Indiana Memory
- Eckhart Public Library, Auburn Indiana
Authorization for Dan M. Link to investigate troubles in the coal mining industry in West Virginia on behalf of the United States Coal Commission. Typed document with the signature of "John Jays Hammond, Chairman", probably a rubber stamp.
- United States. Coal Commission
Coal mines and mining--West Virginia
Coal mines and mining--Kentucky