Author: | Holtz, John C. |
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Year: | 1968 |
Document Type: | N/A |
SUDOC: | I 28.23:7074 |
Series: | United States Bureau of Mines Reports |
Report Number: | R. I. 7074 |
Subject: | Tunnels -- Ventilation. |
Link: | http://digital.library.unt.edu/ark:/67531/metadc38714/ |