Daniele Bourdais; Malcolm Hope; Teresa Huntley; Clive Thorpe. (1997). Essor: Student's Book. Oxford University Press.
Chicago-viite (17. p.)Daniele Bourdais; Malcolm Hope; Teresa Huntley; Clive Thorpe. Essor: Student's Book. Oxford University Press, 1997.
MLA-viite (9. p.)Daniele Bourdais; Malcolm Hope; Teresa Huntley; Clive Thorpe. Essor: Student's Book. Oxford University Press, 1997.
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