APA (7th ed.) Citation

Ashley, G. H. (1917). Oil resources of black shales of the Eastern United States. Department of the Interior, United States Geological Survey.

Chicago Style (17th ed.) Citation

Ashley, Geo. H. Oil Resources of Black Shales of the Eastern United States. [Washington, D.C.]: Department of the Interior, United States Geological Survey, 1917.

MLA (9th ed.) Citation

Ashley, Geo. H. Oil Resources of Black Shales of the Eastern United States. Department of the Interior, United States Geological Survey, 1917.