00949nam a2200253Ia 450000100060000000300050000600500170001100800410002801000150006903500200008404000190010405000310012308200230015408600170017710000340019424501280022826000620035630000240041849000950044250400280053765000350056565000260060083000690062687521BIBL20160527204129.0790724s1979    dcua     b   f000 0 eng    a 79018531   a(OCoLC)05333971  aDLCcDLCdm.c.1 aTN23b.U43 no. 8416aTN288  a622/.08 sa622/.260 aI 28.23:841610aTandanand, Sathit.wcn2Local10aDevelopment of a mechanical roof breaker for ground control in longwall operations under massive roofcby Sathit Tandanand.0 aWashingtonbDept. of the Interior, Bureau of Minesc1979.  a20 p.bill.c27 cm.1 aReport of investigations - United States Department of the Interior, Bureau of minesv8416  aBibliography: p. 17-18. 0aGround control (Mining)2Local 0aRock mechanics2Local 0aReport of investigations (United States. Bureau of Mines)v8416.