Cita APA (7th ed.)

Johnson, K., & Morrow, K. (1979). Approaches: A language activation course for intermediate students. Cambridge University.

Cita Chicago (17th ed.)

Johnson, Keith, i Keith Morrow. Approaches: A Language Activation Course for Intermediate Students. Cambridge: Cambridge University, 1979.

Cita MLA (9th ed.)

Johnson, Keith, i Keith Morrow. Approaches: A Language Activation Course for Intermediate Students. Cambridge University, 1979.