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room-work | |||
room mining | |||
pillar mining; forewinning | |||
chain wall (im Kohlenbergbau); chainwall (im Kohlenbergbau); chamber working; pillar-and-chamber (working); pillar and stall (method); pillar working; punch-and-thirl; room and pillar; room-and-pillar method (mining); room-and-rance (im Kohlenbergbau); rooming; roomwork |
Kammerbau: 1 phrase in 1 subject |
Mining | 1 |