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Continue to ChatLongwall top coal caving design for thick coal seam in very poor strength surrounding strata - https://avesis.itu.edu.tr/yayin/1d123e18-b45c-47be-a449-b6b0ac8508b2/longwall-top-coal-caving-design-for-thick-coal-seam-in-very-poor-strength-surrounding-strata