Cita APA (7th ed.)

Helfgott, R. B. (1974). Labor economics ([1st ed.].). Random House.

Cita Chicago (17th ed.)

Helfgott, Roy B. Labor Economics. [1st ed.]. New York: Random House, 1974.

Cita MLA (8th ed.)

Helfgott, Roy B. Labor Economics. [1st ed.]. Random House, 1974.