The Middle Devonian strata of southern Illinois
By: [by] William G. North.
Series: Illinois. State Geological Survey. Circular; 441; Circular (Illinois State Geological Survey) ;; 441.
Publisher: Illinois State Geological Survey
Published: 1969
Place of publication: Urbana
Language: eng
Number of pages: 45
Subjects: Geology, Stratigraphic -- Devonian; Geology -- Illinois
Notes: Bibliography: p. 39-40.
Cover title.