Author: | Paul, J. W. |
---|---|
Year: | 1927 |
Document Type: | USBI |
Issuing Agency: | U.S. Dept. of Commerce, Bureau of Mines, |
SUDOC: | C 22.11:6042 |
Series: | Information circular / Bureau of Mines ; |
Report Number: | 6042 |
Subjects: | Coal mines and mining--Safety measures |
Mine timbering | |
Link: | https://hdl.handle.net/2027/mdp.39015086471433 |