Tohutoro APA (7th ed.)

Low, O. (1979). Certificate of proficiency English practice. Edward Arnold.

Tohutoru Kātū Chicago (17th ed.)

Low, Ona. Certificate of Proficiency English Practice. Londres: Edward Arnold, 1979.

Tohutoro MLA (9th ed.)

Low, Ona. Certificate of Proficiency English Practice. Edward Arnold, 1979.