Pleistocene stratigraphy of northwestern Pennsylvania /

by White, George Willard, 1903-1985, Totten, Stanley M., Gross, David L.
Harrisburg, PA. : Pennsylvania, Bureau of Topographic and Geological Survey, 1969

Pleistocene stratigraphy of northwestern Pennsylvania /

by White, George W. (George Willard), 1903-1985, Totten, Stanley M., Gross, David L.
Harrisburg, PA. : Pennsylvania, Bureau of Topographic and Geological Survey, 1969

Geology and hydrology of the Mercer quadrangle, Mercer, Lawrence and Butler Counties, Pennsylvania /

by Poth, Charles W.
Harrisburg [Pa.] : Pennsylvania, Bureau of Topographic and Geologic Survey, 1963

Geology and hydrology of the Neshannock quadrangle, Mercer and Lawrence Counties, Pennsylvania /

by Carswell, Louis D.
Harrisburg [Pa.] : Pennsylvania, Bureau of Topographic and Geologic Survey, 1963