Cita APA (7a ed.)

Low, O. (1977). A new certificate of proficiency English course (3rd. ed.). Edward Arnold.

Cita Chicago Style (17a ed.)

Low, Ona. A New Certificate of Proficiency English Course. 3rd. ed. London: Edward Arnold, 1977.

Cita MLA (8a ed.)

Low, Ona. A New Certificate of Proficiency English Course. 3rd. ed. Edward Arnold, 1977.