APA (7th ed.) Citation

Smith, H. M. (1927). Study of intermediate base crude oil. [publisher not identified].

Chicago Style (17th ed.) Citation

Smith, Harold M. Study of Intermediate Base Crude Oil. Washington, D.C.: [publisher not identified], 1927.

MLA (9th ed.) Citation

Smith, Harold M. Study of Intermediate Base Crude Oil. [publisher not identified], 1927.