Geology of the oil and gas fields of the Hilliards quadrangle : (advance report) /

by Sherrill, R. E. (Richard Ellis), 1899-1952
[Harrisburg, Pa.] : Commonwealth of Pennsylvania, Dept. of Internal Affairs, Bureau of Topographic and Geological Survey, 1939

Oil and gas developments in Pennsylvania in 1989 /

by Harper, John A.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1990

Oil and gas developments in Pennsylvania in 1981 /

by Harper, John A.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1982

Oil and gas developments in Pennsylvania in 1982 /

Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1983

Oil and gas developments in Pennsylvania in 1978 /

by Piotrowski, Robert G.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1979

Oil and gas developments in Pennsylvania in 1974 /

by Lytle, William S.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geologic Survey, 1975

Oil and gas developments in Pennsylvania in 1986 /

by Harper, John A.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1987

Oil and gas developments in Pennsylvania in 1984 /

by Harper, John A.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1985

Oil and gas developments in Pennsylvania in 1972 /

by Lytle, William S.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geologic Survey, 1973

Oil and gas developments in Pennsylvania in 1973 /

by Lytle, William S.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geologic Survey, 1974

Oil and gas developments in Pennsylvania in 1977 /

by Heyman, Louis, Cozart, Cheryl L.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1978

Oil and gas developments in Pennsylvania in 1980 with ten year review and forecast /

by Harper, John A.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1981

Oil and gas developments in Pennsylvania in 1983 /

by Harper, John A.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1984

Oil and gas developments in Pennsylvania in 1964 /

by Lytle, William S.
Harrisburg, PA. : Pennsylvania, Bureau of Topographic and Geologic Survey, 1965

Oil and gas developments in Pennsylvania in 1976 /

by Lytle, William S.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geologic Survey, 1977

Oil and gas developments in Pennsylvania in 1985 /

by Harper, John A.
Harrisburg, Pa. : Pennsylvania, Bureau of Topographic and Geological Survey, 1986

Oil and gas developments in Pennsylvania in 1970 /

by Lytle, William S., Heyman, Louis, Kelley, Dana R.
Harrisburg, Pa : Pennsylvania, Bureau of Topographic and Geological Survey, 1971