APA (7th ed.) Zitazioa
Comfort, J. a. (1994). Speaking effectively: Developing speaking skills for business english. CUP.
Chicago Style (17th ed.) Zitazioa
Comfort, Jeremy...[et al]. Speaking Effectively: Developing Speaking Skills for Business English. Cambridge: CUP, 1994.
MLA (9th ed.) Zitazioa
Comfort, Jeremy...[et al]. Speaking Effectively: Developing Speaking Skills for Business English. CUP, 1994.
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