00925cam a22002411  4500001001300000003000400013005001700017008004100034010001700075035001900092040004000111050001900151100002800170245006700198260009400265300004000359490002000399500006900419500007600488504003900564651003400603650004600637gs 39000361 DLC20260227111345.0780817s1939    pauab    b    000 0 eng c  ags 39000361   a(OCoLC)4149251  aU.S. Geol. Survey. LibrarycPUdDLC00aQE158.P55bL421 aLeighton, Henry,d1884-10aGuidebook to the geology about Pittsburgh,cby Henry Leighton.  aHarrisburg, Pa.,bDepartment of internal affairs, Topographic and geologic survey,c1939.  a35 p.billus., map, tables.c23 cm.0 aBulletin G,v17  aAt head of title: Pennsylvania Geological survey, Fourth series.  aOn cover: Commonwealth of Pennsylvania. Department of internal affairs.  a"Selected bibliography": p. 34-35. 0aPittsburgh (Pa.)vGuidebooks. 0aGeologyzPennsylvaniazPittsburgh Region.