Citazione Stile APA (7a Edizione)

Low, O. (1975). A new certificate of proficiency English course whit practice and test papers (3a. ed.). Edward Arnold.

Citazione stile Chigago Style (17a edizione)

Low, Ona. A New Certificate of Proficiency English Course Whit Practice and Test Papers. 3a. ed. Londres: Edward Arnold, 1975.

Citatione MLA (9a ed.)

Low, Ona. A New Certificate of Proficiency English Course Whit Practice and Test Papers. 3a. ed. Edward Arnold, 1975.