Cita APA (7a ed.)

Schaefer, V. G. (1941). Safety supervision. McGraw-Hill.

Cita Chicago Style (17a ed.)

Schaefer, Vernon G. Safety Supervision. New York [etc.]: McGraw-Hill, 1941.

Cita MLA (9a ed.)

Schaefer, Vernon G. Safety Supervision. McGraw-Hill, 1941.