Παραπομπή σε μορφή APA (7η εκδ.)

Crews, F. C. (1994). Speaking effectively: Developing speaking skills for business English. Cambridge University Press.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Crews, Frederick C. Speaking Effectively: Developing Speaking Skills for Business English. Cambridge: Cambridge University Press, 1994.

Παραπομπή σε μορφή MLA (8th εκδ.)

Crews, Frederick C. Speaking Effectively: Developing Speaking Skills for Business English. Cambridge University Press, 1994.