Hutchison S. Susan. (2008). Premium. B1 level: Woorkbook with key. Harlow, Longman, 2008.
Cita Chicago (17th ed.)Hutchison S. Susan. Premium. B1 Level: Woorkbook with Key. Harlow, Longman, 2008, 2008.
Cita MLA (9th ed.)Hutchison S. Susan. Premium. B1 Level: Woorkbook with Key. Harlow, Longman, 2008, 2008.
Atenció: Aquestes cites poden no estar 100% correctes.