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39 (XXXIX) — 1928-1929
U.S. Accidents, 59, 102, 103, 267, 360.
U.S. Bureau's Activities, 290.
U.S. Coal, 41, 65, 154, 405.
U.S. Coke, 38.
U.S. Concentrated Mining, 21.
U.S. Mineral Resources, 123.
Under-cutting Machine Mining, 42.
Underground Communication, 42.
Underground Conveying, 164, 182.
Underground Fires, 103, 193, 209, 271, 314.
Underground Illumination, 122.
Underground Supports, 156.
Unemployment Schools for Boys, 108.
Upcast, Covering, 175, 391.
Utilisation, Low Grade Fuel, 104.
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