Cita APA (7th ed.)

English Language Services & English language services. (1964). English 900.: Book three. Macmillan.

Cita Chicago (17th ed.)

English Language Services i English language services. English 900.: Book Three. London: Macmillan, 1964.

Cita MLA (9th ed.)

English Language Services i English language services. English 900.: Book Three. Macmillan, 1964.