Author: | Arentzen, Einar M. |
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Year: | 1946 |
Document Type: | USBI |
Issuing Agency: | U.S. Dept. of the Interior, Bureau of Mines, |
SUDOC: | I 28.27:7390 |
Series: | Information circular / United States Department of the Interior, Bureau of Mines ; |
Report Number: | 7390 |
Subject: | Coal-mining machinery |
Link: | https://hdl.handle.net/2027/mdp.39015074128045 |