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Elkton-Wilmington folio ; Maryland-Delaware-New Jersey-Pennsylvania
(Geological Survey (United States), 1920)
Warren folio, Pennsylvania-New York
(Geological Survey (United States), 1910)
Trenton folio, New Jersey-Pennsylvania
(Geological Survey (United States), 1909)
Somerset-Windber folio, Pennsylvania
(Geological Survey (United States), 1934)
Sewickley folio, Pennsylvania
(Geological Survey (United States), 1911)