APA (7th ed.) Citation

Porter, W. W. (1938). The practical geology of oil. [publisher not identified].

Chicago Style (17th ed.) Citation

Porter, William W. The Practical Geology of Oil. [Houston, Tex.]: [publisher not identified], 1938.

MLA (9th ed.) Citation

Porter, William W. The Practical Geology of Oil. [publisher not identified], 1938.