Jones, L. (1993). Progress to Proficiency: Student's Book (New edition.). Cambridge: Cambridge University Press.
Trích dẫn kiểu ChicagoJones, Leo. Progress to Proficiency: Student's Book. New edition. Cambridge: Cambridge University Press, 1993.
MLA CitationJones, Leo. Progress to Proficiency: Student's Book. New edition. Cambridge: Cambridge University Press, 1993.
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