| Year: | 1974 |
|---|---|
| Document Type: | USBI |
| Issuing Agency: | U.S. Dept. of the Interior, Bureau of Mines, |
| SUDOC: | I 28.27:8630 |
| Series: | Information circular / United States Department of the Interior, Bureau of Mines ; |
| Report Number: | 8630 |
| Subjects: | Mining engineering--Congresses |
| Coal mines and mining--United States--Congresses | |
| Link: | https://hdl.handle.net/2027/mdp.39015078516443 |