Map of Beaver County : Showing outcrops of the Pittsburgh, upper Freeport, and Kittanning coals.

Map of Beaver County : Showing outcrops of the Pittsburgh, upper Freeport, and Kittanning coals. J.P. Lesley, State Geologist. I.C. White, Ass't Geologist. 1876. Julius Bien & Co. Photolith. New York. Lane S. Hart, State Printer. Grand atlas, Division I, Part I. Sheet no. IV.

Geological Survey of Pennsylvania

1876

1885

Second Geological Survey of Pennsylvania

1:125 000

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