Hopkins D. Diana & Cullen P. Pauline. (2007). Cambridge Grammar for IELTS: Grammar reference and practice. Cambridge, Cambridge University Press, 2007.
Cita Chicago Style (17a ed.)Hopkins D. Diana y Cullen P. Pauline. Cambridge Grammar for IELTS: Grammar Reference and Practice. Cambridge, Cambridge University Press, 2007, 2007.
Cita MLA (9a ed.)Hopkins D. Diana y Cullen P. Pauline. Cambridge Grammar for IELTS: Grammar Reference and Practice. Cambridge, Cambridge University Press, 2007, 2007.
Precaución: Estas citas no son 100% exactas.