Cita APA (7a ed.)

English Language Services. (1966). International Trade. Collier-Macmillan.

Cita Chicago Style (17a ed.)

English Language Services. International Trade. London: Collier-Macmillan, 1966.

Cita MLA (9a ed.)

English Language Services. International Trade. Collier-Macmillan, 1966.