01021cam a22002651i 4500001001300000003000400013005001700017008004100034010001700075035001900092040003800111042001200149050002500161100003300186245009900219260002500318300004800343410008300391500012300474504003300597650002700630650003800657650004300695999001700738gs 41000156 DLC20260227111347.0800825s1941    xx            000 0 eng c  ags 41000156   a(OCoLC)6651478  aU.S. Geol. survey Lib.cPLhSdDLC  apremarc00aQE157b.A293 no. 1261 aLaird, Wilson Morrow,d1915-14aThe upper Devonian and lower Mississippian of southwestern Pennsylvania /cby Wilson M. Laird.  a[Harrisburg :c1941]  a1 p. l., 23 p. :btables, diagrs. ;c23 cm.10aPennsylvania.bBureau of Topographic and Geologic SurveytProgress reportv126  aAt head of title: ... Commonwealth of Pennsylvania.  Dept. of internal affairs ... Topographic and geologic survey ...  a"Literature survey": p. 2-4. 0aGeologyzPennsylvania. 0aGeology, StratigraphicyDevonian. 0aGeology, StratigraphicyMississippian.  c27743d27743