TR  / RI-8628 <br/>
Chekan,G. J. <br/>
       INVESTIGATION OF LONGWALL GATEROAD ROOF SUPPORT CHARACTERISTICS AT POWHATAN NO.4 MINE INSTRUMENTATION PLAN 
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 .-  U.S. Bureau Of Mines, Washington, D.C.,  1902 
 .- 9 . 
.- ( U.S.Bureau Of Mines Report Of Investigations  Bmri-8628   
<br/>Bound With: Ri-8620 
<br/><u>Subject Headings:</u> <br/>United States Department Of Interior;
<br/><U>Author Added Entry: </u><br/>Babich,D. R.;
<br><U>Copy Details:</u><br> Acc. No.: <b>TR292</b>, Full Call No.: TR RI-8628,   Item type:  Technical Report , Location: General Stacks, <br><b>------------------------- --------------------- ------ --------- ------- ------- --------- -------- </b><br>