| Year: | 1960 | 
|---|---|
| Document Type: | USBI | 
| Issuing Agency: | U.S. Dept. of the Interior, Bureau of Mines, | 
| SUDOC: | I 28.27:7962 | 
| Series: | Information Circular / Bureau of Mines ; | 
| Report Number: | 7962 | 
| Subjects: | Electricity in mining | 
| Coal mines and mining--Electric equipment | |
| Link: | https://hdl.handle.net/2027/mdp.39015077564097 |