Underground Mine Communications (In Four Parts). 1. Mine Telephone Systems (Including Articles on a Coaxial-cable Telephone System and Conventional Telephone Equipment)
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| Description | information circular published in 1977 |
| Author/s |
author: anonymous |
| Publication date | January 1, 1977 |
| Language | English |
| Country of origin | |
| Wikipedia link | |
| Copyright status | |
| Missing/wrong data? | Edit Wikidata item |