The upper Devonian and lower Mississippian of southwestern Pennsylvania
By: by Wilson M. Laird.
Published: 1941
Place of publication: [Harrisburg
Language: eng
Number of pages: 23
Subjects: Geology -- Pennsylvania.; Geology, Stratigraphic -- Devonian.; Geology, Stratigraphic -- Mississippian.
Notes: "Literature survey": p. 2-4.
At head of title: ... Commonwealth of Pennsylvania.  Dept. of internal affairs ... Topographic and geologic survey ...