Timber withdrawing and devices used for this purpose in some coal mines /
| Main Authors: | , |
|---|---|
| Format: | Government Document Book |
| Language: | English |
| Published: |
Washington, D.C. :
U.S. Dept. of Commerce, Bureau of Mines,
1933
|
| Series: | Information circular (United States. Bureau of Mines) ;
6722 |
| Subjects: |