Author: | Parkinson, Howard E. |
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Year: | 1974 |
Document Type: | BMRA |
Issuing Agency: | U.S. Bureau of Mines, |
SUDOC: | I 28.23:7976 |
Series: | Report of investigations / United States. Bureau of Mines ; |
Report Number: | 7976 |
Subjects: | Mine communication systems |
Telephone in mining | |
Link: | https://hdl.handle.net/2027/mdp.39015078484386 |