The Geology of Pennsylvania Geological Survey of Pennsylvania Published: 1858 Total Pages: 716 Get eBook
Geological Survey of Pennsylvania Geological Survey of Pennsylvania Published: 1895 Total Pages: 1008 Get eBook
Annual Report on the Geological Survey of the State of Pennsylvania Geological Survey of Pennsylvania Published: 1888 Total Pages: 344 Get eBook
Geological Survey of Pennsylvania Pennsylvania. State Geologist (1874-1890) Published: 1895 Total Pages: 140 Get eBook
Geological Survey of Pennsylvania: pt. 1. Carboniferous formations, by J.P. Lesley, E.V. d'Invilliers, and A.D.W. Smith. pt. 2. Bituminous coal fields, by E.V. d'Invilliers. The new red of Bucks and Montgomery Counties, by B.S. Lyman Geological Survey of Pennsylvania Published: 1895 Total Pages: 756 Get eBook