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GB564212A
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Improvements relating to pit props and the like
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GB551766A
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Improvements in and relating to roof supports for mines
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US2242961A
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Device for shoring or spragging
|
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GB525845A
|
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Improvements in or relating to pit props and the like
|
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GB518084A
|
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Improvements in or relating to devices for shoring or spragging
|
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US2208885A
|
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Collapsible pit prop and the like
|
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GB514185A
|
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Improvements in or relating to collapsible pit props and the like
|
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GB514197A
|
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Improvements in or relating to collapsible pit props and the like
|
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US2197567A
|
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Bracket for attachment to pit props, stanchions, beams, and the like
|
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GB494315A
|
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Improvements in or relating to brackets for attachment to pit props, stanchions, beams and the like
|
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GB457122A
|
|
Improvements in and relating to roof supports for mines
|
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US1979503A
|
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Pit prop
|
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GB391915A
|
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Improvements in or relating to pit props
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