| Author: | Davis, Charles Albert, |
|---|---|
| Year: | 1913 |
| Document Type: | USBM |
| Issuing Agency: | U.S. Dept. of the Interior, Bureau of Mines, |
| SUDOC: | I 28.7:55 |
| Series: | Technical paper / United States Department of the Interior, Bureau of Mines ; |
| Report Number: | 55 |
| Subjects: | Briquets (Fuel) industry--Germany--Cologne Region |
| Coal mines and mining--Germany--Cologne Region | |
| Lignite industry--Germany--Cologne Region | |
| Lignite--Germany--Cologne Region | |
| Link: | https://hdl.handle.net/2027/mdp.39015077561044 |