University of Cambridge. (2014). Cambridge preliminary English test 7 audio CD set: Authentic examination papers from Cambridge ESOL. Việt Nam: Fahasa Printing Factory.
Chicago-tyylinen lähdeviittausUniversity of Cambridge. Cambridge Preliminary English Test 7 Audio CD Set: Authentic Examination Papers From Cambridge ESOL. Việt Nam: Fahasa Printing Factory, 2014.
MLA-viiteUniversity of Cambridge. Cambridge Preliminary English Test 7 Audio CD Set: Authentic Examination Papers From Cambridge ESOL. Việt Nam: Fahasa Printing Factory, 2014.
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